How casino slots work

Online casino sites to play on real money

The casino does have an edge over the player. This is true of every casino game, in fact. The casino gets its edge using math and large numbers. Every bet on every casino game offers a lower payout than the actual odds of winning. For example, in roulette, the odds of hitting a specific number are 37 to 1. But a bet on a specific number only pays off at 35 to 1. It doesn’t take a genius to figure out how the casino makes its profit in that situation, does it?

How slot machines & coin slots work

Slot machines are the most popular games in any casino, but a lot of people don’t have a clear understanding of how they work. In fact, some people have an out-and-out misunderstanding of how they work, while others are more than willing to take advantage of the gambling public’s ignorance in such matters. See our page about slot machine myths for about what we think of those people.

The purpose of this page is to explain in some detail how a slot machine actually works. Once you have an understanding of the actual inner workings of the game, you might find yourself less (or more) attracted to this type of game, depending on your temperament. Slots can be a lot of fun, but they’re extraordinarily profitable for the casino for several reasons, not least of which is how they actually operate.

Are online slots rigged? If online slots were rigged, then you can guarantee that almost all of them would be closed down by now. It’s one of the biggest concerns people have when playing online, and it’s why we only recommend reputable casinos here at VSO. The top gaming jurisdictions such as UK, malta and gibraltar ensure that fair and secure gaming requirements are in place, and this gives each person the same percentage chance of winning.

Return to player (RTP) is the factor that decides how much the slot pays out. If the slot has an RTP of 96%, then for every $100 that is gambled, the slot will payout out $96. This is regulated and independently tested to make sure you have a safe environment to play it.

We want all of our readers to make the right decisions when it comes to playing games online, so follow our recommendations and eliminate any risk of encountering rigged slots.

Slot machines use a random number generator. Early slot machines were mechanical (think coin slots), but they still used a random number generator, in the same sense that a roulette wheel, a deck of cards, or a pair of dice are also random number generators. Modern slot machines use a computer to generate random numbers, and these determine the outcomes of the game.

The important thing to remember is that the results are truly random. The game doesn’t work on any kind of cyclical basis, and slot machine jackpots don’t become due. Slots don’t get hot or cold, either. They only seem to, and only then in retrospect. It’s not something you can predict, any more than you can predict with any degree of certainty what the next card will be when dealing a deck of cards.

For example, in roulette, the odds of hitting a specific number are 37 to 1. But a bet on a specific number only pays off at 35 to 1. It doesn’t take a genius to figure out how the casino makes its profit in that situation, does it?

Slot machines work the same way.

Slots usually have three reels but sometimes also have five reels. The reel is the image that spins in the front of the machine. It has multiple symbols on it, and if you line up certain combinations of symbols, you win money. The less likely it is to line up a particular set of symbols, the higher the payout on that particular combination.

For decades, these reels were literally large metal hoops, but now that slot machines are powered by computers, they’re more often just images on a video screen. Even in the case of slot machines with actual reels, the outcome is determined by the random number generator inside the computer.

Where those reels stop are called, naturally, “stops”. Reels can stop on a symbol or on a blank space between those symbols. On early slot machine games, each symbol would have an equal chance of coming up, but now that computers are running the show, the odds can be convoluted. You might have a cherry on a reel that comes up on average once every 50 spins, while an orange might come up on average once every 5 spins, or any other combination you can think of.

Early slot machines might have only had 10 stops per reel, but now it’s common to have between 30 and 50 stops per reel. The more stops you have on a reel, the easier it is to offer really large jackpots. For example, if you have a game with 10 stops on each reel, with an equal chance of landing on each stop, then your chances of winning any particular combination are 1/10 X 1/10 X 1/10, or 1/1000. If you have a payout larger than 1000 units, you’re losing money on that game.

Modern computers can adjust those odds using a weighting system.

The weighting is what determines how likely a particular stop is to be picked. Suppose you have a slot machine game with 10 symbols, but one of those symbols is special and only comes up once every 100 spins. The odds of getting 3 of that symbol are 1/100 X 1/100 X 1/100, or 1/1,000,000. You could theoretically offer a payout of $1 million on that combination and still break even over the long run. Casinos love that kind of action, and so do players.

Another symbol might be programmed to come up half the time, so your chances of hitting that symbol might be as low as ½ X ½ X ½, or 1/6. If that pays out at 2 to 1, the casino still makes a significant profit, but the player feels like she’s winning on a pretty regular basis.

The par sheet determines the odds. Every modern slot machine is designed with a par sheet which specifies the weightings for each stop on the reel, including the blanks. That par sheet makes the odds and the house edge for a slot machine game a known quantity—for the casino. Gambling companies keep these par sheets under wraps, though, so players never really get a clear idea of what the odds, the house edge, or the payback percentage is.

One final term you should understand is “payback percentage”. This is a mathematical prediction of how much money the machine will “pay back” over an infinite number of spins. For example, if a machine is programmed to have a 97% payback, over enough spins, the average should come close to winning $3 out of every $100 put into the machine. Casinos distinguish between the theoretical payback percentage and the actual return on the machine, but you can count on one thing. Slots are immensely profitable for the casinos.

Online slots guide – slot machines explained

Slots are currently the most popular casino games. The basic rules of this game haven’t changed since 1899 when charles fay assembled the first slot machine. A player bets and spins a set of reels with symbols. Each of these spinning reels stops at a random position. The player wins if the reels stop in a way that they make a line of the same symbols. The rarer the winning symbols, the higher the amount of the win. The size of the win for each winning combination is defined in the paytable.

Nowadays the randomness of mechanically stopped reels has been replaced by random numbers generated by a computer, but the principles remain same. These principles of randomness are honoured by every licensed game provider. The randomness of slots has several very interesting consequences, and it is important for every smart slots player to understand them.

"the principles of randomness are honoured by every licensed game provider."

How slots work

The majority of online slots still use reels to represent the result of each spin. Despite the fact that the reels are rendered by a computer, the game math under the hood still has 3 to 5 sets of symbols (virtual reels) that stop at random positions. Why change something that has worked fine for years, right?

Modern online slots have a lot of new features which wouldn’t be possible with mechanical reels. Expanding wilds, scatters, free spins, bonus rounds, and others.

Random number generator (RNG)

There is one thing all fair slot games have in common: the outcome of each round is based exclusively on a random number provided by a random number generator (RNG). The random number generated by the RNG "tells" the reels when to stop and therefore decides the outcome of the game. That means that the same game with the same random number must always give the same outcome.

The higher the size of your bets, the higher (usually) the RTP of your betting system. We assume that all the other rules of the betting system remain the same.

How Slot Machines & Coin Slots Work, how casino slots work.

Your win (or loss) in every round is determined purely by your luck. The outcome isn’t influenced by your previous wins/loses, nor the wins/losses of other players, nor by anything predictable. It’s just you and electromagnetic noise in the RNG – simply pure gambling.

The outcome of a game isn’t influenced by your previous wins/loses, nor the wins/losses of other players, nor by anything predictable.

This reminds me that I should explain how rngs work. Modern rngs used in online casinos are dedicated hardware devices that generate random numbers out of electromagnetic noise. It’s like an old television without signal – a lot of black and white dots. Black pixel is 0, white pixel is 1. Take a photo of a small part of a TV screen, convert the pixels into 1s and 0s, write them into a text file and you have a random number.

RNG hardware generates thousands of random numbers every second. So on one hand, you will change the outcome of the next round if you press the start button one second later. However, on the other hand, you have no chance to predict whether the outcome will be better for you or not. So the fair randomness remains.

How do casinos make money?

Now you may ask: if slots are not manipulated, how do casinos make money on them?

The answer is simple: slot games are designed in a way that they pay out less than players bet in the long run.

Imagine a simple game: you give me $1 and flip a coin. If you get heads, I’ll give you $1.50 back. If you get tails, you lose. It’s quite obvious that the chances are on my side. You can win if you are lucky and play only a few rounds, but I have a clear advantage in the long run. The randomness of this game is fair, but the long-term chances aren’t.

Slots are similar, just much more complicated. The math of a slot game is defined by:

Sets of symbols on virtual reels

Win sizes in the paytable

Rules and probabilities of all bonus features

Settings of all bonus features

Game math combined with fair random numbers gives the casino a long-term advantage over players. And that is how casinos make money.

"game math combined with fair random numbers gives the casino a long-term advantage over players."

Slot machines myths

Now that I have explained how fair slots really work, it is time to bust several popular myths about slots.

Myth 1: "slots have cycles of winning combinations. You can win by observing these cycles and by jumping in during a winning part of the cycle."

This is a myth, as slots really work based on fair random numbers. The advantage of the casino is hidden in the game math, and there is absolutely no need to complicate the entire system with any type of cycle.

In reality you may observe hot streaks and cold streaks. But that’s just a result of natural randomness and these streaks are absolutely not predictable.

Myth 2: "slots are programmed not to pay after a big win and to pay more when they’re full of money."

This is a myth which probably comes from the days of standalone slots which paid out to the winning player directly. But it was as much of a myth then as it is now. If you won more money than the slot machine could pay out, you got the remainder from casino staff.

Modern slot machines are connected to a central server and all wins are paid out by casino staff, so there is no need to keep the amount of cash in a slot machine in mind. Random numbers work just fine and this myth is invalid.

Myths 3 & 4: "autoplay features pay less than clicking the spin button manually" & "pulling the ledger on one-armed bandits gives you better odds than pressing the spin button."

Both of these myths make no sense to those who know how online slots work. The game math remains the same, and random numbers remain fair, whether you use the autoplay feature, the ledger or the spin button.

How slot machines are programmed

This is my favorite part as in the past, I have personally developed software solutions for a game provider. :)

Running a casino and creating good games requires different sets of skills. Moreover, players like to play the same games over and over. Those are probably the reasons why specialized companies which focus solely on creating casino games were established. It’s also the reason why you can play starburst slot in so many casinos. Netent (the company which created starburst) is an independent company.

This is briefly how it works:

Casino initiates your gaming session.

Your browser communicates with the servers of the game provider, not with the casino.

The random number and round outcome is also generated by an independent company (the game provider).

Casino just confirms your bets and is notified about your wins by the game provider.

There is one very important implication of this: if you are losing too much while playing a game from a reputable game provider, you can be quite sure that it’s just your bad luck. Even if you play your favorite game at an unknown casino, you are quite safe, in terms of game fairness (though you may be not safe in terms of actually getting your money – use our casino reviews to find a reputable casino that actually pays the money out, even when you win big). I’ve had gaming sessions with an RTP below 50% in the past.

To make it clearer, here is a picture of how 1 spin in a casino game works:

And all this usually happens within less than 200 milliseconds :).

Slots RTP and volatility/variance

RTP and volatility are the 2 most important mathematical characteristics of a slot game. They basically influence how much and how often you win. However, it is a bit more complicated, so I will try to explain them to you.

Return to player (RTP)

RTP (return to player, also payout ratio or payout percentage) is the long-term statistical rate of the total money won divided by the total money staked. The phrase "long-term statistical rate" may sound complicated, so here is the more human-friendly explanation:

If a game RTP is 96%, it means that if you start with $1,000,000,000 and then play 1,000,000,000 rounds at $1 each, then you should end up with approximately $960,000,000 dollars.

If you play just a few hundreds rounds, your current return may vary from 30% up to 1000%. But the more rounds you play, the more likely you’ll be closer to the statistical RTP of the slot game. That’s why I used such big numbers in the example above.

The most common RTP of online slots is around 96%. Some slots like blood suckers have an RTP up to 98%.

"the most common RTP of online slots is around 96%."

RTP is a very popular characteristic in online slots because it can be expressed as a single number. It is easy to compare, and the most of the popular game providers declare the RTP of each slot game. Then it’s easy to write articles like "top 10 best paying slots".

RTP can be used for various simplified calculations, like how much you can expect to lose from a bonus while rolling it over.

Volatility

These simplified calculations are good to impress your friends while drinking beer. But for more serious calculations (like those which we did in our bonus hunting article), you’ll need to count volatility as well.

Volatility of slots is quite a complicated concept so I’ll start with an explanation of volatility in roulette:

When betting on color you can win 2 times your bet and you win quite often (18 of 37 rounds).

When betting on number you can win 36 times your bet but you win only in 1 in 37 rounds.

The volatility of roulette can be easily expressed in numbers from 2 to 36, depending on what type of stake you take. Higher volatility means that your individual wins will be higher. However, you will win less often and you are more likely to lose your entire budget faster.

Volatility of slots

Volatility of a slot game can’t be expressed as a single number, as you can win thousands of different win amounts as a result of the many different winning combinations. I have found out that the most accurate way to present slot volatility is a chart like this:

This chart shows the share of total wins paid out as various multiples of the bet. For example, the chart above displays that 15% of total wins are paid out as individual wins with sizes ranging from 2x to 5x the bet, and 10% of total wins are paid out in higher individual wins from 200x to 500x the bet.

How to calculate volatility

As volatility can’t be expressed as a single number, game providers usually only classify slot into either "low", "medium", or "high" volatility categories. These categories can’t be effectively compared, nor used in any calculations, but they can give you at least a basic idea about the volatility of the game you are about to play.

Finding the real slot volatility (in the form of the chart presented above) is a very difficult task. Basically, you have to reverse-engineer the reel set of a game and properly estimate probabilities of other special game features. Even for me, this is a task that would take a day or more (depending on the slot’s complexity).

Slot volatility can be roughly estimated from the paytable and the reel set. Look for the highest winning combination. What is the chance of hitting it? How much will you win?

I personally like high volatility games as you can win higher amounts, so you can have the same thrill with lower stakes. And lower stakes mean that you’ll statistically lose less. This effect can easily compensate for a slightly lower RTP.

For example, lotteries often have an RTP of 50%, but the chances of winning the jackpot and becoming a multimillionaire keeps the masses playing it. Even my mom sometimes buys a lottery ticket and imagines what she would do if she won. And she would never, ever throw a single cent into a slot machine.

When not taking into account the lottery, slots are the most volatile type of game you can play in a casino. The advantage of high volatility can beat the high RTP of games like blackjack or roulette. To learn more about volatility and RTP and how they influence your chances to win, read this article.

How to increase the volatility of a slot machine

Here are some tricks you can use if you wish to increase slot volatility:

Use the double up button (black/red). RTP remains same and you can easily increase the game volatility to desired values simply by gambling until you win a big enough amount.

Change the number of paylines to 1 and increase the bet per line. The chances of hitting a win in that particular line are lower, but you can expect much higher wins. Try that with our online free slots in demo mode if you don’t believe me ;).

These are basic tips that can help you. However, if you really want to know how to get the most out of playing slots, read the following article.

How do slot machines work?

Players love slots machines because they are easy to play and casinos love them because they are much more profitable than any other game in their establishment. Their profitability comes from the way they work as well as the sheer volume of players who play on them. What is fascinating is, even if lots of players love online slots, most of them do not understand how they work, and not a single reputable casino will give you this information as it is a trade secret.

So, how do casino slots actually work?

Well, as you may know, all casino slots have reels that spin during each round unless you play on autospin, which is a topic for another day. Most slots come with three reels although more and more new casinos now come with up to five reels. These five-reel video slots are marketed as giving you better odds of winning but that is not right due to the way the machines are set up.

Each of the symbols on the reels is “weighted”. Weighting simply determines how likely a symbol is to be picked. Symbols that are heavily weighted, usually those of a higher value, appear less often making the odds of landing them very low. What this means is that due to the amount of time it would take someone to win, a casino can place a huge jackpot on landing the weighted symbol on lots of video slots and break even before it is won.

No, casinos are not ripping you off

Some players, when they go for too long without winning might start thinking the casino is ripping them off. This is not true (as long as you’re not playing on a unlicensed casino, which then might be rogue). Every single game in a casino has its odds with some of them having worse odds than others. It is therefore important that you understand the odds of a video slots game before you commit to playing for the jackpot. There is one tip you could follow to achieve this.

One rule of thumb is, the bigger the jackpot or price, the lower the chances of you winning it. Although most slot machines have smaller prices, they pay out more frequently. It, therefore, makes sense for you to play at these machines, win small amounts a lot of times and slowly work your way up. Doing this is better than trying for the big price, losing lots of money and leaving before hitting the jackpot.

Understanding how slots work is beneficial

Every player who wants to make some money playing slots has to understand how they work. Having this information will help you choose the best slot games and ensure you do not lose too much money. If you cannot find this information by looking at the machines, an internet search should let you know what games are less likely to eat up all your money. Lastly, remember playing is all about fun so do not take it too seriously. And while you’re at it, why don’t you start gambling with someone else’s money? A no deposit casino will give you a few £ to play for free, and slotsia is the place to find the best offers!

How slot machines work

Originally, casinos installed slot machines as a diversion for casual gamers. Unlike traditional table games (such as blackjack or craps), slot machines don't require any gambling knowledge, and anyone can get in the game with a very small bet.

This idea proved to be a monstrous success -- slot machines eventually moved off the sidelines to become the most popular and the most profitable game in town, bringing in more than 60 percent of the annual gaming profits in the united states.

The technology of slot machines has also changed a lot over the years. The classic mechanical designs have been almost completely replaced by computer-controlled machines. But the game has remained the same. The player pulls a handle to rotate a series of reels (typically three) that have pictures printed on them. Winning or losing is determined by which pictures line up with the pay line, a line in the middle of a viewing window. If each reel shows the same winning picture along the pay line, you win (certain single images are sometimes winners as well). The amount you win -- the payout -- depends on which pictures land along the pay line.

In this article, we'll find out what sets the reels in motion in modern slot machines as well as in the old mechanical models. We'll also see what determines the odds of winning on a slot machine and look at some popular variations on the traditional game.

The classic slot machine design works on an elaborate configuration of gears and levers. The central element is a metal shaft, which supports the reels. This shaft is connected to a handle mechanism that gets things moving. A braking system brings the spinning reels to a stop, and sensors communicate the position of the reels to the payout system. A coin detector initially registers that a coin has been inserted and unlocks a brake so the handle can move.

There are any number of ways to arrange these elements, and manufacturers have tried dozens of approaches over the years, so we'll focus on one representative design. The basic design includes three reels mounted on a central shaft. The central shaft also supports three notched discs, which are connected to the three reels. A second shaft below the central shaft supports a kicker, a piece of metal comprising three paddles. The kicker paddles are lined up so they can push against the notches on the three discs. The second shaft also supports a series of connected stoppers, teeth that lock into the notches on the discs.

The kicker and the stoppers are both connected to springs, which hold them in a standby position. The kicker is held in place behind the discs, while the stoppers are held up against the discs, locking them into place.

When you pull the handle on a slot machine, these parts do a lot of work. We'll look at exactly what happens in the next section.

How slot machines work from a player’s perspective

Introduction to how slot machines work

In these series of posts, I continue to answer the most common questions about slot machines asked via google searches. This post explains the simple question of how slot machines work.

In this post, I will discuss the operational components of a slot machine from the point-of-view of a slots player. Meaning, the various interface areas on the front of a slot machine. These player interface areas include:

Service light

Bonus display (optional)

Pay table

Players club

Results

Play console

Ticket in, ticket out (TITO)

Additional relatively minor interface areas are not listed or shown below. These areas are the locations audio speakers, audio volume control (optional), display lights, lever arm, and a hearing aid jack to accommodate those with a hearing disability.

Keep reading … or listen instead!

Service light

A slot machine’s service light is generally located at the very top of a slot machine to be easily visible to casino employees. Because of this uppermost location, it’s also known as the candle within slots terminology.

Slots players can switch on the service light by activating the service button on the player console. Or, it will enable by itself if the player wins a hand pay jackpot or the slot machine develops a service fault. Faults might include lack of paper, a full cash-in condition, mechanical or electronic tampering, or an internal electronic failure such as CPU overheating, etc.

Modern casinos have a slot attendant call/dispatcher communication system using a headset and microphone. This setup is helpful for spotting problems on the casino floor. An activated service light automatically notifies the casino operating system. The casino dispatcher then informs the slot attendant responsible for that section of the casino.

Once the notification is sent out, a lit candle is of little practical use. At best, it guides the responding slot attendant the last few feet to the customer needing attention and, also, provides some reassurance to the waiting customer.

Slots players may activate the candle for a multitude of reasons. In general, they do so to deliberately call a slot attendant to their location, for any of a host of reasons only limited by imagination.

Pro-tip #1: service light

Sometimes slots players need to leave a slot machine briefly but don’t want to give it up to someone else. If this break is relatively brief, say 10-15 minutes, use the service button to call over a slot attendant. The slot attendant can temporarily lock up the slot machine at the request of the player.

The slot machine can be unlocked later by the player via insertion of only their service card … or after 10-15 minutes when the temporary lockout automatically expires. For the specific length of lockout times, ask any slot attendant at your casino.

Bonus display area

If a specific slot machine has a bonus round available, then it will often have a second display area. Video slots may use the same primary display screen but abruptly display the bonus round game theme instead. However, video slots most often have a secondary display screen available for bonus rounds.

The bonus display area is optional and dependent upon the specific slot machine model. The location of this bonus display varies. More often than not, it is high up on the slot machine to be viewable by other players from a distance.

Casinos offset their losses by offering slot machines with bonus round display visible from a distance. Frankly, wins on these highly visible and usually loud bonus displays are seen by many. This obvious win encourages other casino patrons to play slot machines.

Pro-tip #2: bonus round

Bonus rounds generally cannot be activated unless that slot machine’s maximum credits are bet. By not betting maximum credits, the player automatically lowers their odds of winning. If betting maximum credits on a specific denomination slot machine is not affordable, pick another affordable slot machine. I discuss this approach in detail at choosing slot machines.

Pay table area

The pay table area lists information on the jackpot amounts for specific reel combinations. It can also display some or all of the game theme rules. This area may be permanently displayed on the slot machine, or possibly only available through an interactive series of images available by touchscreen.

In either case, all possible wins may or may not be displayed. Sometimes the list is highly abbreviated, and displays only the highest jackpots, due to space limitations. Other times, mainly with touchscreen displays, a series of images can be switched between to view every possible winning combination.

However, pay tables typically provide the highest value jackpot. Slot machine game themes with multipliers or “wild” reel symbols have their most top value jackpots being the result of these reel symbols. Alternatively, it may not show all multipliers or “wild” symbols in the tabulated list of win-reel combinations. Instead, they may be in writing along the edge of the paytable interface area.

But, with large touchscreens has come the capability to provide full paytable information along with game theme rules. Some slot machines now have this feature and, perhaps, more will have it in the future.

Many paytables show the number of credits that would be won for a specific combination of reel symbols. Or, they may show a monetary amount. In either case, these tables have separate columns for winning combinations dependent upon how many credits are bet. The far – right column typically shows the winning jackpots available when betting maximum credits.

Some examples of credit and denomination combinations are:

1-credit slot machines having a $100 denomination

3-credit slot machines having a $5 denomination

5-credit “quarter slots” having a $0.25 denomination

300-credit “penny slots” have a $0.01 denomination

Pro-tip #3: pay tables

Frankly, learning the paytable of any slot machines played is a relatively easy way to improve the odds of winning at slots. Many typical slots players believe there is no skill involved in winning at slot machines. Casinos gently foster this misunderstanding, as it is to their benefit. Don’t fall for it.

Traditionally, slots players find it acceptable to play slot machines with visual succinct paytables. Frankly, casinos would instead have their customers spend their time playing a game they don’t understand .

The casino isn’t making money if a player spends time studying or reading until they do understand rather than playing the machine.

One easy-to-learn skill to improve the odds of winning at slots is choosing which slots to play based on their paytables. I discuss this in detail at choosing slot machines.

Players club area

The players club area contains a card reader, numbered keypad, and a small display. A security feature of players club cards is for players to choose a PIN to enter when they wish to access their player account.

Newer-style slot machines have a touchscreen display, which removes the need for a physical keypad. Meaning, it’s part of the touchscreen display.

Bets can be made on a slot machine without a players’ club card. At most casinos, it typically is not required. Neither is the PIN needed to play the device or view basic information. For example, a running total of reward points earned during the current play session is generally on display.

The PIN is required, however, to:

Access certain portions of player’s casino account

Transfer banked funds

Activate “free play” provided by the casino as a complimentary gift

Results area

The results interface area is where the reel combinations are seen after making a bet. Whether a video slot machine or a slot machine with physical reel, this is where the results of a bet are provided.

Interpreting whether a reel combination is a winner requires an understanding of the paytable. This result is fundamental to how slot machines work.

Of course, the slot machine will immediately display the results. A small display beneath the reels shows:

The total amount of money or credits available in the machine

How many credits most recently bet

The jackpot amount won if any

Jackpots are usually in credits, where each credit equals the denomination of the machine rather than the amount bet, as well as a monetary amount.

Player console

The play console typically has physical buttons, a cash/ticket reader, and a ticket printer. The buttons include:

Cash out for requesting the removal of any player funds in the machine

Service to request a casino attendant

A series of buttons for selecting the number of credits to bet, or placing the maximum possible bet

Cash out for removing any remaining bankroll

Repeat to making another bet for the same credit(s)

Denomination to select a specific bet denomination (optional)

The player console may have several possible button configurations, dependent upon the model of the slot machine. Given how often game themes are switched to maintain the interest of players over time, it is common for player consoles to be standardized over many machines within a casino.

Also, it is becoming common for consoles to have embedded displays visible through their semi-transparent button covers. This array of small screens are linked together to show visually stunning composite images displayed across the entire array of buttons.

Ticket in, ticket out (TITO)

By the beginning of the 21st century, the use of coins was removed from casinos. This removal was for the sake of convenience of both the casino and customers. Both had issues with handling so many coins. Customers because of the difficulties inherent with carrying so much weight, but also gambling delays due to full (or empty) slot machine coin hoppers.

Casinos had issues with coins as well, including customer complaints due to delays caused by a full (or empty) slot machine coin hopper. This inconvenience was a coin logistics issue, which also included higher costs of maintaining a larger vault space and coin processing equipment and services. As casinos became more popular, coins became more difficult for everyone.

As a result, ticket-in, ticket-out technology was pulled into casinos. They are now integral to how slot machines work. This automation is the same technology that was beginning to be seen in automated teller machines (atms). Once proven out, this slot machine technology was here to stay like so many others.

Summary of how slot machines work

I’ve discussed the operational components of a slot machine from the point-of-view of a slots player. This explanation of how slot machines work included the various player interface areas on the front of a typical slot machine.

There are additional relatively minor interface areas. These areas include audio speakers, audio volume control (optional), display lights, lever arm, and a hearing aid jack to accommodate those with a hearing disability.

How slot machines work

Aka, how a specific payback is achieved

Вђњmichael bluejay's comprehensive explanation of how slot machines work [is], in my opinion, the best one out there.Вђќ вђ”gaming the odds

NOTES:
(1) this page covers normal slot machines (aka "class III"). Many native american casinos instead use "class II" slots based on bingo or the lottery because local laws don't allow regular slots. Class II machines look pretty much the same on the outside as regular slots, and you still get a random result, the machine just arrives at that random result a bit differently from what's described below.
(2) this page covers traditional slot machines. The new skill-based slots are covered on a separate page.

No popups, no download, no registration, no B.S., just the game. One click and you're in.

Slots are random

Before you see how slots work, you simply have to understand that the outcome of each spin is random. This is a pretty easy concept, but many people just refuse to believe it. If you're not convinced that slots are random, then see my article on how slot machines are random first, then come back here. Don't worry, I'll wait.

Picking the symbols

On a slot machine, a random number generator (RNG) picks a random number for each reel, which each number matching a stop on its reel. Then the machine directs the reels to stop on the spots selected by the RNG.

Note that by the time the reels are spinning, the game is already over. The RNG has already selected the stops, and the reels spin sort of as a courtesy to the player. Slot machines don't even need visible reelsвђ”you could just put your money in and the machine could tell you whether you how much (if any) you won. Wrap your head around that one for a minute. The presence of the visible reels makes no difference in the gameвђ”they're just there to show you what the computer already picked.

How the stops are selected

A typical non-progressive video slot has dozens of stops per reel. An electro-mechanical slot uses an (invisible) "virtual reel" of 64 to 256 stops, which are mapped to the 22 stops on the physical reel. The physical reel isn't big enough to hold all the stops that are needed, so it's the big one that's used in the computer program. (example source)

If you saw a worker open up an electro-mechanical slot machine you might see a reel like the one on the right, if it were unfolded. There are various symbols spread across 22 stops. Yes, the blanks count as stops. You might think that since there are 11 blanks you have a 50% chance of hitting one, and since there's only one jackpot symbol you have a 1-in-22 chance of getting it. But it doesn't work that way, because we're not really working with a 22-stop reel. We're really working with an invisible reel of like 128 or so stops, controlled by the computer. The computer will pick a number from 1-128, each of which is mapped to a specific symbol. Here's a hypothetical map for the reel shown at right:

Selected number	symbol picked	total no. Of symbols
1-73	blank	73
74-78	cherry	5
79-94	bar	16
95-107	double bar	13
108-118	triple bar	11
119-126	red 7	8
127-128	jackpot	2

Say the computer picks #53. That's a blank, and it tells the reel to stop on a blank. If it picks #75, then it tells the reel to stop on a cherry. If it picks #127, then the reel tops on the jackpot symbol.

Most of the numbers are for the lower-paying symbols, so that's what's more likely to get chosen. That's what we mean when we say the reel is weighted. Some symbols are more likely to be chosen than others, even if they appear the same number of times on the physical reel.

So you don't really have a 1 in 22 chance of hitting the jackpot symbol on this reel. Your odds are actually 2 in 128, or 1 in 64.

And of course, the most likely symbol is a blank. On our sample machine, you have a 73 in 128 chance (57%) of drawing one of those.

Speaking of blanks, when the computer picks a blank, it actually picks a specific blank. Same for the other symbols that appear on the reel multiple times, like cherries and certain bars. The table above was simplified to make things easier to understand, but now that we've come this far, let's now look at how every single position on the reel might be weighted.

Selected
number number
of chances 1 cherry 1-2 2 2
3-7 5 3 вђ” 8-12 5 4
13-17 5 5 7 18-25 8 6
26-30 5 7 вђ” 31-35 5 8
36-41 6 9 cherry 42-43 2 10
44-49 6 11 == 50-56 7 12
57-62 6 13 cherry 63 1 14
64-69 6 15 = 70-75 6 16
76-81 6 17 вђ” 82-87 6 18
88-93 6 19 оћоћ 94-104 11 20
105-115 11 21 jackpot 116-117 2 22
118-128 11

The fourth column (number of chances) shows the weighting. We've got a 2 in 128 chance of landing on the first stop (a cherry), and an 8 in 127 chance of hitting stop #5, the red 7. Notice how the blanks surrounding the jackpot symbol, #20 and #22, are heavily weighted. They're more likely to be selected, resulting in the "near-miss" effect. You think you just almost got the jackpot symbol, but it's really an illusion. You weren't close at all. It's like the blanks above and below the jackpot have little magnets on them.

So far we've talked about only one reel, though most slots have three or five, and each reel is actually weighted differently. As you go from reel to reel the weighting gets heavier, so you're more likely to hit higher paying symbols early on. By the third reel the higher-paying symbols are even less likely. This results in another kind of near-miss effect: how many times have you gotten JACKPOT, then another JACKPOT, and then. A blank? After the first two hits you're holding your breath for the third reel, but in reality your odds are poorer for getting that third jackpot symbol than they were for getting either of the first two symbols. However, for the rest of this discussion, we're going to assume that each reel is in fact identical in order to make the math easier.

Hitting the jackpot

So now that we know the weighting of the reels, we can answer that elusive question: what are the odds of hitting the jackpot? Here's the answer. Assuming we have three identical reels as listed above, then the odds of getting the jackpot symbol on any reel is 2/128. The probability of hitting the jackpot on all three reels is 2/128 x 2/128 x 2/128 = 1 in 262,144. (if you played fast at 800 spins for 8 hours a day, you'd hit the jackpot on average once every 41 days.) this in fact is the odds of hitting the jackpot on red white & blue. (see more on jackpot odds.)

Calculating the payback

Now that we know the weighting of the reels, we can calculate the payback for this machine, which the percentage of money the machine would pay back over an infinite number of spins. Of course you can't play for an infinite amount of time, but the point is, the longer you play, the closer your return will come to what the payback suggests.

Our slot has the following paytable.

Bluejay bonanza slot machine paytable
symbols	payout
jackpot (3 JP symbols)	1666
7 7 7	300
оћ оћ оћ	100
= = =	50
вђ” вђ” вђ”	25
3 of any bar	12
3 cherries	12
2 cherries	6
1 cherry	3

To find the payback of the machine, we multiply the probability of each winning hit times the payout for that hit, then add them all up, as shown in the following table. I included a "how calculated" column if you're interested in seeing how I derived the probabilities. The numbers I use there came from the first table, above ("total no. Of symbols" column).

So this is a 96.3% machine, meaning that if you played it forever, you'd get back 96.3вў for every $1 you put into it. Of course you can't play it forever, and in the short-term anything can happen, but the longer you player, closer your return will come to 96.3%вђ”meaning you will have lost 3.7% of all the money you bet.

Of interest is that the small payouts account for most of the payback. The single cherry alone provides nearly a third of all the money you get back from the machine. Same for "any bar / any bar / any bar". The jackpot itself comprises less than 1% of the total payback.

Note that some figures are not exact due to rounding.

The RNG is constantly picking numbers

The RNG is always working, even when you're not playing, picking hundreds of random numbers per second. (NV gaming regulations, technical standards, 1.400) the moment you press the button or pull the lever, the RNG picks its 3 or 5 numbers for your play. So if someone hits a jackpot on a machine you were just playing, relax, you wouldn't have gotten it had you kept playing, because you would have hit SPIN at a slightly different time than they did. Every fraction of a second you delay in hitting the SPIN button results in a different combination.

The reason the machine constantly picks numbers is so that no one can discern any pattern in the number-picking process and therefore predict a winner. It's extremely unlikely that anyone could do so even if the RNG didn't keep picking random numbers all the time, because the number of random numbers in a complete cycle is astronomical, but having the RNG pick numbers all the time removes even the fantastically remote possibility that anyone could predict the outcome.

Par sheets

Slot makers create a "par sheet" for each slot which lists the reel symbols and the paytable. From this the payback can be calculated, and a programmer can write the computer code for the slot. This data is similar to the tables I provided above for my fictional slot. I have a separate page about par sheets, along with several actual examples.

Near misses

Earlier we saw how the symbols on electromechanical slots are weighted. There are only 11 blanks on the physical reel, but chances the RNG will pick a blank is much higher than 1 in 11. In fact, it will favor the blanks immediately above and below the jackpot symbol. Hitting these blanks gives players the illusion that they almost landed the jackpot symbol, because the jackpot symbol is physically close to the payline. But it's not mathematically close. In reality, the player wasn't close to landing the jackpot symbol on the payline at all.

As you might expect, research shows that the near-miss effect keeps players playing longer. (journal of gambling studies)

The wizard of odds cites an unnamed source who said that nevada regulations say that a stop on a reel can't be weighted more than six times more than either stop next to it. (link) however, I scrutinized regulation 14 and can't find any such requirement.

Video slots show the actual reels rather than virtual reels. As such, the kind of near-miss described above won't artificially appear on video slots. (in theory, there might be some video slots that use virtual reels, but I haven't seen any evidence of this.) however, video slots use another method to make a near-miss effect: they put fewer jackpot symbols on the 4th and 5th reels vs. The 1st, 2nd, and 3rd reels. When players line up the symbol on the first three reels they'll feel they were close to getting a 4th and maybe 5th symbol, but the reality is that it's much harder to get those right-hand symbols.

In 1988, it was discovered that certain machines were using a different, illegal kind of near-miss technology. The slot would first choose the stops randomly, and if it was a losing combination, rather than showing the actual combination selected, it would choose another combination to display, which was more likely to show jackpot symbols just above or below the payline. (source)

Do I have free will in the bonus round?

In a bonus round where you can pick from multiple boxes which reveal a prize, players often wonder, "does it matter which box I pick? Are the various prizes truly scattered among the boxes, or am I gonna get (say) 10 credits no matter which box I picked?"

For the answer to that we turn to the authority on these kinds of questions, the wizard of odds, who says: "based on seeing par sheets and speaking to industry insiders I can confidently say that if the alternative choices are shown at the conclusion of a bonus round then the game is honest about them. In other words the prizes were randomly determined and what you see at the end is truly how they were hidden. However in games where the alternative choices are not shown the odds are likely similar to a prize wheel, with lower probabilities for the higher wins." (source)

Play slots online

I suggest you play something other than slots because the slot odds are so bad. You could also play online with fake money, because then it doesn't matter if you lose. A good casino for free-play is bovada, since it requires no download and no registration. (if you see a registration box, you can close it and continue without registering.) you can play with real money too, though I hope you won't (or at least won't bet more than you can comfortably afford to lose).

How slot machines work from a player’s perspective

Introduction to how slot machines work

In these series of posts, I continue to answer the most common questions about slot machines asked via google searches. This post explains the simple question of how slot machines work.

Service light

Bonus display (optional)

Pay table

Players club

Results

Play console

Ticket in, ticket out (TITO)

Keep reading … or listen instead!

Service light

Pro-tip #1: service light

Bonus display area

Pro-tip #2: bonus round

Pay table area

Some examples of credit and denomination combinations are:

1-credit slot machines having a $100 denomination

3-credit slot machines having a $5 denomination

5-credit “quarter slots” having a $0.25 denomination

300-credit “penny slots” have a $0.01 denomination

Pro-tip #3: pay tables

The casino isn’t making money if a player spends time studying or reading until they do understand rather than playing the machine.

One easy-to-learn skill to improve the odds of winning at slots is choosing which slots to play based on their paytables. I discuss this in detail at choosing slot machines.

Players club area

Newer-style slot machines have a touchscreen display, which removes the need for a physical keypad. Meaning, it’s part of the touchscreen display.

The PIN is required, however, to:

Access certain portions of player’s casino account

Transfer banked funds

Activate “free play” provided by the casino as a complimentary gift

Results area

Interpreting whether a reel combination is a winner requires an understanding of the paytable. This result is fundamental to how slot machines work.

Of course, the slot machine will immediately display the results. A small display beneath the reels shows:

The total amount of money or credits available in the machine

How many credits most recently bet

The jackpot amount won if any

Jackpots are usually in credits, where each credit equals the denomination of the machine rather than the amount bet, as well as a monetary amount.

Player console

The play console typically has physical buttons, a cash/ticket reader, and a ticket printer. The buttons include:

Cash out for requesting the removal of any player funds in the machine

Service to request a casino attendant

A series of buttons for selecting the number of credits to bet, or placing the maximum possible bet

Cash out for removing any remaining bankroll

Repeat to making another bet for the same credit(s)

Denomination to select a specific bet denomination (optional)

Ticket in, ticket out (TITO)

Summary of how slot machines work

Slot tournaments – how do they work?

By: will connington october 2, 2018

What are slot tournaments? Slots are among the least competitive games you could think of – just how does a tournament work? Well, there is actually nothing complicated at all. You compete against the other players by simply spinning your slot. At the end of the tournament, the player who has accumulated the most winnings receives the grand prize. That’s the gist of it – the rules rarely get more complex than that, and there is no specific preparation required other than getting familiar with the slot you will be playing in advance. We’ll cover everything that you need to know in the next few paragraphs. We’ll also talk about online slot tournaments which can be a tad more complicated.

Basic format of a slot tournament

When on a night out at your favourite casino, you may have noticed a portion of the venue blocked by ropes, and a number of people spinning the slots at a furious speed. That’s how a slot tournament looks from the side.

In a slot tournament, you usually receive a number of credits from the casino, and have a set amount of time to play through them. Your wins are tracked, and the player who has accumulated the most coins – or points – wins the tournament.

Such tournaments create a great sense of camaraderie as they gather slot fans from all over the region – but there is little time for interaction during the tournament itself, as you have to focus on your own slot. This means that there is no direct conflict, and you shouldn’t expect a battle royale of some sort. Of course, an obnoxious loud-mouth might ruin your fun from time to time. Sadly, you will encounter such individuals in all alleys of life, including casinos where you’re supposed to relax.

Are slot tournaments free?

Wait, if the casino is giving you credits, is the tournament free? Well, you know what they say about free lunch.

In most cases, slot tournaments have a fixed entry fee – a ‘buy-in’. It would be something like £25 – £50. The funds gathered this way usually make up the prize for the tournament winner. Most players grow quite fond of this system, because this actually sets the limit on how much they will spend gambling in advance.

Sometimes, casinos do organize free slot tournaments. Those are great, of course – you get to play without any investment, and might just nab the prize! The casinos usually view such tournaments as a means of attracting more regular customers, and you should expect much lower prizes than in paid competitions.

Additionally, many casinos organise private tournaments for their more loyal customers. You can enter those only upon receiving a special invite. The quality can vary across most venues, but casinos with strong brand usually tend to make those impromptu competitions memorable and fun for their regulars.

Rules, tips and strategy

Under this basic format, slot tournaments are determined solely by luck. This is fine – after all, the history of slots shows that they got so popular because they didn’t require too much skill in the first place. That said, experienced players do hold certain advantages which might mitigate their luck to a degree. Playing at a slot tournament differs from regular games because you are not using your own money – this means that you should bet as much as you can! Considering that only your wins are calculated, you would maximize your chances if you play through as much of your budget as possible.

This might seem like a silly suggestion, but keep in mind that you have a set time limit, and there is a certain physical overtime required to insert your coins and pull the lever. A lot of inexperienced players lose speed as they grow tired, or simply stick to their casual tempo – this is a mistake, because any credit you fail to wager contributes nothing to your final result!

Another mistake players do is to lose time celebrating their wins. Of course, joy sometimes overwhelms you, and it isn’t bad to voice it, but the clock does not stop ticking only because you scored a good win, and the other players are also racking up their results.

The same basic principle applies to online tournaments, of course – things might be a little more innovative there, but you should maintain a constant speed and use up as much of your allotted budget as possible within the timeframe. This means that spending a little time before the tournament to get familiar with the slot you will be playing on and trying out the controls for yourself will prove invaluable in the long run.

Online slot tournaments

Online operators have also been playing attention to the success of the slot tournaments and trying to adapt them to the pc platform. Some casinos like 32red hold regular tournaments on specific online slot games, while others like royal panda organise thematic promotional campaigns at different times of the year.

Online slot tournaments can break from the basic mould described in the above paragraphs. Sometimes they don’t even have a set time limit – after all, this can be a hassle for many of the participants. Once more, there might be an admission fee required, but there are also alternative variants.

Certain tournaments take place over longer periods of time, and don’t award you with free credits in advance. Instead, you accumulate score with your normal playthroughs. At the end of the tournament – which can be a 20-minute session or a 1-month slog – the best player is awarded with a cash prize.

Notice the use of the word ‘best’. If an online tournament breaks from the set mould of playing through a number of credits, the win conditions might change too. Sometimes the players accumulate points by scoring a streak of wins – this is a good format, because it means that it doesn’t matter how large your bet is!

Avalon, tomb raider and starburst are among the more common titles you can expect to find listed for tournaments.

Other types of online slot tournaments – the terminology explained

If you like to change your online gambling venues, you might encounter more innovative tournament variants. Here are some of the main types:

Signup freeroll: this light competition is a good way to get to know your way around your new online casino. Some operators organise such events as a little extra to the welcome bonus that you receive. However, you shouldn’t expect a large prize pool. Usually it is only the new players that get to take part for a £50-£100 first place reward. More importantly, such events might secure you a free invite to other tournaments with more lucrative prizes. Take advantage of such events and use them to see what a tournament feels like and whether you enjoy the casino’s format.

Scheduled tournaments: your basic slot tournament. It is advertised in advance, and you need to register before the beginning and play a buy-in fee.

Sit and go tournament: those are open-seat tournaments. There is a limited number of places, and you need to sign in to take one. As soon as all the seats are taken, the tournament kicks off – but keep in mind that sometimes there can be a significant wait before enough players are gathered.

Sit and go tournament: those are open-seat tournaments. There is a limited number of places, and you need to sign in to take one. As soon as all the seats are taken, the tournament kicks off – but keep in mind that sometimes there can be a significant wait before enough players are gathered.

Comped tournaments: the term might be familiar to some of you. Comp points are loyalty rewards that some online casinos give you for playing on their games with real money. As you can imagine, these slot tournaments are the equivalent to the VIP events we mentioned above, where only loyal customers are invited.

Reloader tournaments: those are the equivalent of ‘re-buys’ in poker tourneys. In such tournaments, the buy-in allots you specific time for play, but you can rebuy for an additional fee and start over if you bust out. Such tournaments are usually featured with microgaming slots.

Extender tournaments: similar to the above, but you get the chance to buy add-ons here. The add-ons boost your final score. Most players choose to take up this option if they want to maximise their odds of winning, but it is perfectly fine to ignore it if you trust in your luck.

Survivor slots tournaments: this tournament uses one of the most competitive formats and introduces an elimination phase. There are different rounds, and only the winner from each stage can move on the face the rest of the winners. Rebuying or adding on is not allowed.

One-shot tournaments: these are single-elimination tournaments. You get a single shot at qualifying for the next stage – there are no rebuys, no add-ons, and no mercy. The battle here is fiercer than the competition for jobs in the UK!

Frequently asked questions about slot tournaments

We hope you found this review of slot tournaments useful. To ensure that we covered everything that you need to know, we researched what questions players ask about the topic. To end this blog post, we have compiled the most frequently asked questions and provided the answers for you.

��‍♂️ what is a slot tournament?

A slot tournament is a competition against other players. You play a specified slot game within a certain timeframe and with a certain number of casino credits. At the end of the tournament, the player with the most accumulated winnings gets a prize.

�� how does a slot tournament work?

A slot tournament works as a competition between slots players. For a set period, any winnings you amass from playing a certain slot will be tracked. Once the tournament ends, the player with the most coins or points wins the tournament. You can find more details about the basic rules of slot tournaments in our dedicated section.

��‍♂️ how to play in a slot tournament?

You play in a slot machine tournament in a land-based casino, you should spin as many times as possible within the set time limit and credits. To play in an online slot tournament, the basic rules are the same. You should check the operator's promotions regularly to find out when slot tournaments will take place and opt in to play.

�� how to win a slot tournament?

Slot tournaments rely on luck. Yet there are some winning tips that can help you improve your chances. These include betting as much of the allotted budget as possible. Another tip is to maintain a constant speed, so you do not waste any opportunities to accumulate winnings.

�� what is a free slot tournament?

A free slot tournament can be entered without spending any of your own cash. Free tournaments can be included as part of a casino's promotional offers. Some operators also provide free slot machine tournaments as a loyalty reward for existing players.

Play slots online with grosvenor casinos

If you’ve just registered with grosvenor casinos, chances are you’re looking to play slots online. With a simple format and fun features, online slots offer a relaxed, low-pressure gaming experience. There’s a wide range of games to choose from with a variety of themes from ancient egypt and lucky leprechauns to hollywood movies and TV gameshows. Each game has its own instructions so even if you’ve never played slots online before, you’ll quickly get to understand which symbols to look out for and how paylines work. Many online slots have free spins rounds where you can spin the reels without staking your cash and exciting features that offer you more chances to win cash prizes.

How to play online slots

So, how do you play online slots? Almost all slot games have the same base instructions - simply click the spin button and the game does the rest!

Slot games do not require any skill or strategy. As wins are down to chance, online slots appeal to all levels of player.

Slot game paylines

To win when you play slots games, you need to match identical symbols in a specific order on the reels. This is called a payline or a win line. Each game will have a different number of paylines. You can see what these are on each in-game help menu. Paylines are often:

In a row

In a zig-zag pattern

In a V shape

Diagonally

The winning symbols for each game vary, and paylines are weighted differently on each spin. When you are playing with real money, your balance will be debited every time you spin the reels. You will also need to decide how much to stake on each payline to make up your total stake.

Some slots do not use paylines and instead pay out based on the number of symbols you land on the reels. With these types of game, you can have over 2,000 ways to win.

Wilds and scatter symbols

Many slots games include wild symbols, where a special symbol substitutes for all other symbols, helping you create a winning line. For example, if the wild symbol is a lion and you have a payline of giraffe-lion-giraffe, the lion counts as a giraffe symbol to create a win.

Scatter symbols can also appear at random, with a variety of outcomes. They do not need to be in a payline to be activated. In both book of ra deluxe and lord of the ocean, the scatter symbol triggers both the bonus round and counts as wild, substituting for all other symbols.

But don't worry about this too much – all our online slots are fully automated, so you just have to click the one button to play.

Free spins on slots

As well as being ultra-simple, people like to play online slots for their special features and bonus rounds. Free spins offer an additional way to win without paying, adding excitement and variety to our games.

How free spins work

Free spins can be triggered in many ways. Often, they are achieved by landing a specific set of symbols, but they can also be awarded at random. You can also get free spins by collecting a number of symbols and filling up a ‘free spins meter’ inside the game.

For instance, in book of ra deluxe if 3 book symbols land on the reels, you’ll be taken to the free spins feature, where 1 symbol is selected to expand across the reels for multiplied wins across 10 free spins. The lucky lady’s charm online slot offers a free spins bonus in a similar manner – 3 crystal balls on the reels will trigger 15 free spins and your stake multiplier will be trebled for the duration of the bonus round.

Online promotions and free spins bonuses

We often give away free spins as part of our slots promotions, so check out the promotions tab to see what’s on offer this week.

If you’re a new player and can’t decide which slot game to choose, take a look at our range of welcome bonuses, including our £20 bonus offer. Once you’ve deposited, you’ll get extra funds to play any slot game.

Want to play slots on mobile? With grosvenor, it’s easy. Just download the grosvenor casinos app and pick your favourite slot game to get started. We have ios and android versions, so you can play slots and casino games on any of your devices. To never miss a bonus, opt into notifications so you see when our online slots promotions are running.

HOW MECHANICAL SLOTS WORK

Most modern slot games are played on video screens, whether in brick and mortar casinos or online. But slots with mechanical reels still have a loyal following, especially in the united states with its more than a century-old tradition of three-reel games. But today’s mechanical-reel games are software-driven, just like video slots, with a few important things to understand before you play:

Results are determined by a random number generator, which tells the reels what to display.

Symbols are mapped onto a virtual reel.

The frequency with which each symbol lands on a payline is not necessarily proportionate to the number of symbols on the physical reel.

The hit frequency, or percentage of winning spins, does not necessarily correlate to the payback percentage.

Making the maximum bet a mechanical-reel slot allows often brings you the highest payback percentage.

RANDOM NUMBER GENERATOR AND VIRTUAL REEL

For many decades after reel slot machines were invented, the number of symbols on each reel coupled with the payoff on each winner determined the game’s payback percentage.
That’s no longer the case. The random number generator and virtual reel have led to machines where the real game is being played internally, in the machine’s software. When the random numbers have been selected, the game programming tells the reels which symbols to display.

ABOUT RANDOM NUMBERS

It’s said that nothing in the universe above quantum level is truly random, but random number generators are close enough that players can’t discern any repeating patterns, and the long-term percentages are those you would expect from randomly occurring outcomes. Here are a few key points about the RNG:

Rngs use algorithms to calculate their numbers.

Rngs are very fast, generating dozens and sometimes hundreds of random numbers per second.

The RNG keeps running even when the machine is not being played.

The only function of the RNG is to generate random numbers. It doesn’t know how those numbers are used.

The RNG works with a full set of numbers on every spin, so all results are possible on every spin.

How many random numbers are used and how they are mapped onto symbols differs from game to game. So do the entry points to start the next calculation. With more sophisticated rngs, hitting the “bet one coin” button, the “max bet” button or pulling the handle could start the algorithm from different points. Because the RNG works so fast, if you pause slightly before your next play or stop for a few seconds to order a beverage or chat with a neighbor, your result will be different than if you kept at the same pace. That doesn’t mean your result will necessarily be better or worse, just different.

If you leave a machine and someone else takes your place and hits the jackpot, that doesn’t mean you’d have won if you’d stayed. The RNG would be at a different point in its calculations.

ABOUT THE VIRTUAL REEL

The virtual reel makes it possible to have a much larger range of outcomes than if odds were determined by the number of symbols and spaces on a mechanical reel mechanical reels must fit inside a machine’s casing. You can increase a reel’s size from 10 symbols and 10 spaces to 20 and 20, 30 and 30 and so on up to a point, but if you want to drive odds that make a really big jackpot possible, you need more combinations than physical reels alone can handle. Mapping symbols and spaces onto a virtual reel dramatically increases the number of possible combinations.

Let’s keep the arithmetic simple, and say you have a reel with 10 symbols and 10 spaces. The symbols can be the same as the example in chapter 2-1: each reel has one 7, two bars, three cherries and four watermelons.

But instead, let’s map all those symbols and spaces onto a virtual reel, so there are 50 stops on each reel:

A FEW THINGS OF NOTE:

In this example, each like symbol was given the same number of stops on the virtual reel. That doesn’t have to be the case. Cherry no. 1 could be given three stops and cherry no. 2 six stops, or any other number, if that’s what fits the desired odds of the game. Mapping does not have to be identical for each reel. Cherry no. 1 could have three random numbers on reel no. 1, four on reel no. 2 and five on reel no. 3, if that led to the desired odds. On mechanical-reel machines today, the spaces between symbols also are stops. Symbols alone were counted here to simplify the arithmetic for the same of example.

Now let’s compare what the virtual reel does to the number of combinations, compared to the physical reels alone.

With odds determined by the physical reel, the chances of lining up the rarest combination, 7-7-7, are 1 in 1,000, so the jackpot can’t be very large. Even if you keep paybacks very small on other three-symbol combinations, it would be difficult to have a top jackpot of more than a couple of hundred coins. By mapping those symbols onto this simplified virtual reel, the jackpot chances become 1 in 125,000. Now the jackpot can run into thousands of coins, and there’s a lot more room for paybacks on other symbols. Let’s use physical reels and virtual reels to make up pay tables that are identical, except with the jackpot set high enough to bring the total return to 90 percent:

Both those games have odds that would lead to a 90 percent return, but letting the number of symbols on the physical reel dictate the odds leads to a jackpot of not quite 300 coins while using the virtual reel enables jackpot of more than 25,000 coins.

Everything’s easily adjustable with so many possibilities. Game designers can give you a less volatile game by making the jackpot smaller and increase paybacks on lesser winners. There’s not the same kind of wiggle room when you’re dealing with only 1,000 possible combinations.

Combination of a random number generator and a virtual reel determine what symbols and spaces you see on a slot with mechanical reels.

The random number generator operates continuously, even when a machine is not being played, and any change in your timing will lead to a different result.

The virtual reel can make a physical reel behave as if it has many more symbols than it really does, and leads to more possible combinations.

The increase in the number of combinations enables bigger jackpots and more variation in payoffs.

HIT FREQUENCY VS. PAYBACK PERCENTAGE

Winning the most often doesn’t always translate into winning the most money. There are two separate concepts:

Hit frequency is the proportion of spins that pay money to players.

Payback percentage is the proportion of wagers returned to players as winnings.

Let’s start by considering two games with identical pay tables, but different hit frequencies. These are not real games; it’s just an example set up to make the arithmetic that follows easy. Reel stops include blank spaces as well as symbols, but only three of the same symbol form a winning combination. Odds are set so there are 10,000 possible combinations, so what’s listed in this table are the number three-symbol possibilities per 10,000 spins:

We can tell several things from the chart above:

Of 10,000 combinations, game A has 1,336 winners to only 1,005 on game A.

The 1,336 game B winners give it a 13.36 percent hit percentage, to 10.05 percent on game A.

Both the hit frequencies and paybacks per win are the same on 7s, bars and cherries.

The 331 extra melon winners give game B both a higher hit frequency and higher payback percentage.

Per 10,000 coins wagered, each game pays 1,000 on 7s, 3,500 on bars and 3,000 on cherries, for a total of 7,500. But game A pays 1,338 on melons, and game B pays 2,000. That makes the total return 8,838 on game A, giving it an 88.8 percent payback percentage. Game B has a total payback of 9,500 coins for a 95 percent payback percentage.

If these two games were sitting side-by side in the casino, they would appear to be identical. Winning combinations and their paybacks would be displayed, and those are the same. Players would not be able to tell one machine had a higher hit frequency and payback percentage.

ADJUSTING THE PAY TABLE

What if a slots game designer wanted a machine with game A’s hit frequency, but game B’s payback percentage, or game B’s hit frequency but game A’s payback percentage? One route is by adjusting the pay table.

The hit frequencies are still 13.36 percent on game B and 10.5 percent on game B.

The payback on cherries has been changed to 120 on game A, and down from 100 to 80 on game B.

Game B still has a higher hit frequency.

Game A now has a higher payback percentage.

The larger payoffs on cherries are enough to bring game A up to a 95.38 percent payback percentage, just a fraction more than game B paid in the first example. Game B is now down to 88 percent, a fraction less than game A paid earlier. So here, the game with the higher hit frequency is actually the lower payer.

WHAT YOU SEE VS. WHAT YOU GET

In the above example, it looks like you can tell which is the higher payer, because game A both pays more on cherries and has a higher payback percentage. Can a glance at the pay table tell you which game is a higher payer?

The answer to that is no, a look at the pay table can be misleading. Let’s try one more example, in which one game pays more on every winning combination. Once again, we’re using an example with 10,000 possible reel combinations.

From the outside, game A looks like a much higher payer, paying 1,500 vs. 1,000 for game B on three 7s, 150 vs. 100 on 100 on bars, 20 vs. 10 on cherries and 2 vs. 1 on melons.

But internally, out of your view, the hit frequencies also have been changed. Game A now has a hit frequency of only 5.76 percent, while game B has been increased to 25.31 percent.

Let’s look at what that does to the overall payback, adjusting for the number of winners for each three-symbol combo:

Game A pays more on every winning combination but has a lower payback percentage, 90.5 percent vs. 92 percent on game B.

On 2,200 spins, the melons on game B pay only the size as your bet.

On game A, there are only 400 melon winners, but they pay double your bet.

Such a large number of low-paying spins means game B will have low volatility, which has the effect of extending your play.

Games with such a large difference in hit frequency but such a small difference in payback percentage were used to show you the kind of leeway game designers have. If 2,050 melon combinations were used instead of 2,200, the games would have identical payback percentages, but would be vastly different playing experiences.

In that case, you would have a better chance at winning big at game A, but a better chance at extended playing time at game B. Real games are more complex than these examples, but offer the same kinds of different playing experiences.

On real three-reel mechanical slot games, hit frequencies as low as 5.76 percent and as high as 25.31 percent are rare. Real three-reel, single-payline games have hit frequencies that cluster between about 9 and 13 percent. Games with more paylines have higher hit frequencies.

The examples above are to illustrate principles. Real mechanical slots and their math are more complex. Three-reel games usually have more than four symbols, opening more possibilities, and game programmers aren’t confined to using number sets that yield 10,000 combinations – in fact, on big jackpot games, the number sets are much, much larger.

Here are a few additional factors that add complexity, texture and fun to the mechanical-reel portion of modern slot floors:

Many newer three-reel slots have more than one payline.

Games with more than three mechanical reels have a niche in casinos, with five reels often used.

Many three-reel games today also incorporate bonus events.

Games with multiple paylines open more possibilities and add complexity to the calculations. Three lines across the screen plus two diagonals take a game to five lines, and more lines can be created with vs and zigzags, just like on video slots. In recent years, game manufacturers have produced three-reel mechanical games with as many as 27 paylines. Bonus events also add complexity to calculation. A diminishing number of games put all the focus omn the spinning reels. However, many three-reel games incorporate free spins, bonus wheels on top of the games, or secondary video screens to create a hybrid mechanical-video game. Any bonus payouts have to be accounted for in calculating the game’s overall return.

Higher hit frequencies don’t always bring higher overall returns.

A game that looks like a high-payer to a player could actually be a lower-paying game than one with a lower pay table.

Game designers and programmers use a combination of hit frequency and payback per win to get to a final payback percentage.

Additional factors in modern mechanical slots include multiple paylines, using five reels instead of three and incorporating bonus events into the games.

PROGRESSIVE JACKPOTS: STANDALONE, LINKED AND WIDE AREA

Walk through any sizable casino and you’ll see a slot floor lit up by clusters of machines with electronic jackpot signs on top. Penny by penny, the jackpot grows, from $12,355.67 to $12,355.68 to $12,366.69 and beyond. When somebody wins the jackpot, the total on the sign is reset to a base value, then starts building again for the next big winner.

These games with the building prizes are progressive slot machines, and they’ve been favorites of jackpot hunters for decades. The base awards can be small, as in the $250 starting point on 25-cent blazing 7s slot machine from bally technologies, or can be life-changing, with jackpots of millions of dollars in $1 megabucks machines from international game technology.

On games with mechanical reels, there are three basic types of progressives:

Every player should know that on any of these, it almost always takes a maximum bet to be eligible for the jackpot. If you’re playing a dollar machine with a three-coin maximum bet and you wager only $2, you can’t win the progressive award.

Mechanical slots sometimes are set up with multi-tiered progressives and mystery progressives, but those are more common on video slots. They also don’t usually require a max-coins wager to win the jackpot.
You can read more about them in chapter 6: video slot progressives.

STANDALONE PROGRESSIVES

Standalones have jackpots that that build at a single machine.

The lighted jackpot display usually is within the top portion of the top box above the main reels.

A portion of each bet players make at that machine is added to the jackpot.

After a player wins the jackpot, it is reset to the base value to start building again.

Standalone progressive machines usually are in a bank with several machines of the same type.

Each machine has its own jackpot, so, each machine will display a different jackpot amount.

LINKED PROGRESSIVES

Linked progressives electronically link the jackpots at a number of machines in the same casino.

The same jackpot is available to players at any machine in the link.

A portion of each bet players make at any of the linked machines is added to the jackpot.

After a player wins the jackpot, it is reset to the base value for all machines in the link.

Machines in different parts of the casino can be on the same link.

All machines on a progressive link will display the same jackpot.

Sometimes there will be a large lighted sign over the top boxes of several machines in the bank, displaying the jackpot award. Such a display ties the machines together visually, emphasizing that all have the same jackpot. Then ability to link games in different parts of the casino can sometimes confuse players. I was once in a riverboat casino in the state of illinois, playing in the downstairs level, when the jackpot reset on a bank of IGT double diamond machines. No one at the bank had won the jackpot, and players were baffled. It turned out someone had one upstairs, on another double diamond bank on the same link.

WIDE-AREA PROGRESSIVES

Wide-areas are linked progressives on a bigger scale. They link jackpots at machines at different casinos. The biggest jackpots in a casino almost always are wide-area progressives. GT launched megabucks as the first wide-area system in 1986, and IGT remains by far the biggest provider of wide-area progressives with links including wheel of fortune and TV hits (with game themes based on television shows).

Often, a big, bright jackpot stretches above several machines. Displays attract attention from all over the casino.

The same jackpot is available to players at any machine on the link, even if at different casinos.

The jackpot starts at a base value, then a portion of each bet players make on any machine in the link is added.

When a player wins the jackpot, the jackpot is reset to a base value at multiple casinos

All machines on the link display the same jackpot.

When the jackpot display resets on a linked progressive, players know someone, somewhere has struck it rich. The winner might be hundreds of miles away, but you know from the reset that there’s been a big hit. That jackpot is built by players who can be hundreds of miles apart. On the IGT’s megabucks nevada link, a wager made in reno contributes to the jackpot building in las vegas, lake tahoe or anywhere else in the state.

PROGRESSIVE PROS AND CONS

Should you play a progressive slot machine?

The jackpots are the attraction.

They draw in players who are looking for the chance at a win that can change their lives.

Games with smaller base jackpots usually pay more often than bigger jackpot games.

The chance of winning the top prize at megabucks is about 1 in 50 million. Megabucks goes years at a time between jackpot payouts. On the other hand, bally’s blazing 7s, with a base prize of $1,000 on a $1 machine, was designed as a rapid hit game. If there are 10 to 20 machines in a casino, someone will hit the jackpot an average of once every 15 minutes to half an hour. It’s up to you: do you want
to take a long shot at millions, or have a better chance at a much more modest prize?

A larger portion of the overall payback is tied up in the top jackpot than in non-progressive games.

That means progressive machines usually give less back to players in smaller wins, whether through reductions in the pay table or a reduced hit frequency. The chance at a big jackpot is a tradeoff for an increased risk of a rapid bankroll drain.

It’s important to read the machine glass and understand the conditions of the game before you play.

On three-reel mechanical games, it almost always takes a max-coins bet to be eligible for the progressive. If you don’t bet the max, some games will pay you a reduced amount if you line up the jackpot symbols. But on some, called “buy-a-pays” in the slot industry, each coin activates a set of symbols. On a three-coin blazing 7s game, for example, the jackpot 7s are not winning symbols unless you bet the third coin.

Jackpot hunting can be fun and sometimes rewarding, but if your bankroll won’t stretch to betting enough to be eligible for the progressive award, you’re better off at a non-progressive machine.

So, let's see, what we have: learn how slot machines work by reading real facts about casino slots; including the history of slot games and what it takes for you to beat the odds. At how casino slots work

Comments

Bluejay bonanza slot machine
symbols	probability	how calculated	payout	prob. X payout
jackpot (3 JP symbols)	0.000004	2/128 x 2/128 x 2/128	1666	0.7%
7 7 7	0.000244	8/128 x 8/128 x 8/128	300	7.3%
оћ оћ оћ	0.000635	11/128 x 11/128 x 11/128	100	6.4%
= = =	0.001048	13/128 x 13/128 x 13/128	50	5.2%
вђ” вђ” вђ”	0.001953	16/128 x 16/128 x 16/128	25	4.9%
3 of any bar	0.030518	(16+13+11)/128 x (16+13+11)/128 x (16+13+11)/128	12	36.6%
3 cherries	0.000060	5/128 x 5/128 x 5/128	12	0.1%
2 cherries	0.004399	((5/128)x(5/128)x(128-5)/128)x3 (prob. 1st reel x prob. 2nd reel x prob. NOT 3rd reel; then multiply all by 3, to account for the 2 cherries appearing in any of 3 different positions -- 1,2 or 2,3 or 1,3)	6	2.6%
1 cherry	0.108211	(5/128x(128-5)/128x(128-5)/128)*3 prob. 1st reel x prob. NOT 2nd reel x prob. NOT 3rd reel; then multiply all by 3, to account for our single cherry appearing on any one of the three reels	3	32.5%

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