Understanding Casino Slot Machines

• Appendices
• Slots Analysis
• Miscellaneous

Understanding Different Types of Online Slot Machines. We'd be wasting your time if we attempted to categorize all the types of slot machines. Every casino offers a wide range of slots to attract. Understand Different Types of Slot Machines. The next thing you can do is do your own research about the best online slots according to their types. If you've ever wondered how many types of slot machines exist, our blog will come in handy. Mass market is simple enough: It's the average person who walks into a casino and puts money down at a table or into a slot machine. VIP players play on credit and use what are called rolling.

Introduction

When it comes to gambling, the easier a game is to understand the worse the odds usually are. This is certainly the case with slot machines. Playing them is as easy as pressing a button. However, between the high house edge and fast rate of play, there is no quicker way to lose your money in a casino.

Before going further, let me make clear that this page addresses the way slot machines work in most parts of the United States and the world. However, some parts of this page do not apply everywhere. For example, I state that slot machines have a memory-less property, where the odds of every spin are the same. In some places, like the UK, some machines in bars, called 'fruit machines,' have a mechanism that guarantees a certain profit over the short run, which causes the game to go through loose and tight cycles. These games do not have the usual independence property of the major slot makers.

How They Work

Whether you're playing a 3-reel single-line game or a 5-reel 25-line game, the outcome of every bet is ultimately determined by random numbers. The game will choose one random number for each reel, map that number onto a position on the reel, stop the reel in the appointed place, and score whatever the outcome is. In other words, the outcome is predestined the moment you press the button; the rest is just for show. There are no hot and cold cycles; your odds are the same for every spin on a given machine.

Slot machines are just about the only game in the casino where the odds are not quantifiable. In other words, the player doesn't know how the game was designed, so it is difficult to look at an actual game to use as an example. So, to help explain how they work, I created the Atkins Diet slot machine (link). It is a simple, five-reel game with a free spin bonus round, much like IGT's Cleopatra game.

For information on how it works and all the odds, please visit my Atkins Diet par sheet.

For a more complicated example, featuring sticky wilds in the bonus, please try my Vamos a Las Vegas slot machine.

For information on how it works and all the odds, please visit my Vamos a Las Vegas par sheet (PDF).

Odds

The following table shows the casino win for Clark County Nevada (where Las Vegas is) for all slots for calendar year 2012. They define 'slot' as any electronic game, including video poker and video keno. I've found video keno to be about equally as tight as reeled slots, but video poker has a much higher return. So, the return for reeled slots should be higher than these figures.

Clark County Slot Win 2012

Source: Nevada Gaming Control Board, Gaming Revenue Report for December 2012 (PDF, see page 6).

Most players play penny video slots. Based on past research, I find the house edge on those to usually be set from 6% to 15%. In general, the nicer the casino, the tighter the slots.

Advice

While there is no skill to playing slots, there is some skill in selecting which machine to play and ways you can maximize your return. What follows is my advice, if you must play slots at all.

• Always use a player card. Slots may be a lousy bet, but the casinos treat slot players very well. A $1 slot player will probably get comped better than a $100 blackjack player. Of course, don't play for the reason of getting comps. You'll give them a lot more than they'll give you.
• The simpler the game, the better the odds. The fancy games with big signs and video screens tend to not pay as well as the simple games. However, slot players always tell me the fancy games are more fun.
• The higher the denomination, the better the odds. For that reason, it is better to play one coin per line on a 5-cent game than five coins per line on a 1-cent game.
• Don't forget to cash out and take your ticket when you leave. It is easy to forget after hitting a jackpot.
• Try to play slowly and as little as possible to get your fix.
• In some games there is a skill feature, like Top Dollar. In such games, advice is usually offered, which you should take.

Myths and Facts

Just about everything that players believe about slots is untrue. Here are the most common myths and facts. As a reminder, this page is based on slot machines commonly found in the United States. Some machines, like 'fruit machines' found in the United Kingdom work differently.

• Myth: Slot machines are programmed to go through a cycle of payoffs. Although the cycle can span thousands of spins, once it reaches the end the outcomes will repeat themselves in exactly the same order as the last cycle.

  Fact: This is not true at all. Every spin is random and independent of all past spins.

• Myth: Slot machines are programmed to pay off a particular percentage of money bet. Thus, after a jackpot is hit the machine will tighten up to get back in balance. On the other hand, when a jackpot has not been hit for a long time it is overdue and more likely to hit.

  Fact: As just mentioned, each spin is independent of all past spins. That means that for a given machine game, the odds are always the same. It makes no difference when the last jackpot was hit or how much the game paid out in the last hour, day, week, or any period of time.

• Myth: Machines pay more if a player card is not used.

  Fact: The mechanism that determines the outcome of each play does not consider whether a card is used or not. The odds are the same with or without one.

• Myth: Using a player card enables the casino to report my winnings to the IRS.

  Fact: That makes no difference. If you win $1,200 or more they will report it either way. If you have a net losing year, which you probably will, at least the casino will have evidence of it. Such annual win/loss statements may be used as evidence to declare offsetting loses to jackpot wins.

• Myth: The slot department can tighten my game with the press of a button remotely. Thus, you better be nice to the staff and tip them well, or they will use a remote control to have the machine take you down in a hurry.

  Fact: There is now some truth to the myth that the odds of a machine can be changed remotely. Such 'server-based slots' are still experimental and in a minority. Even with server-based slots, there are regulations in place to protect the player from the perceived abuses that could accompany them. For example, in Nevada a machine can not be altered remotely unless it has been idle for at least four minutes. Even then, the game will display a notice that it is being serviced during such changes. (source) Meanwhile, for the vast majority of slots, somebody would physically need to open the machine and change a computer chip, known as an EPROM chip, to make any changes.

• Myth: The machines by the doors and heavy traffic flow areas tend to be loose while those hidden in quiet corners tend to be tight.

  Fact: I've studied the relationship between slot placement and return and found no correlation. Every slot director I've asked about this laughs it off as just another player myth.

• Myth: Slots tend to be looser during slow hours on slow days of the week. However, when the casino is busy they tighten them up.

  Fact: Nobody would take the trouble to do this, even if he could. The fact of the matter is the casinos are trying to find a good balance between winning some money while letting the player leave happy. That is best achieved by slots loose enough to give the player a sufficiently long 'time on device,' as they call it in the industry, with a reasonable chance of winning so he will return to the same casino next time. If the slots are too tight, the players will sense it and be unlikely to return.

  The kind of place you're likely to find tight slots are those with a captive audience, like the Las Vegas airport. So, if the slot manager feels that 92% is the right return for a penny game, for example, he is likely to set every penny game all that way, and keep them that way for years.

Play

Reviews

• Dazzle Me (NetEnt)
• Mr. Vegas (Betsoft)
• Sparks (NetEnt)

Internal Links

• Appendix 1 shows the details and analysis of almost 4000 actual spins on a Reno slot machine.
• Appendix 2 shows an example of the virtual reels behind a hypothetical slot machine and how the average return is calculated.
• Appendix 3A: 2003 Las Vegas slot machine rankings.
• Appendix 3B: 2002 Jean/Primm slot machine rankings.
• Appendix 3C: 2002 Tunica slot machine rankings.
• Appendix 3D: 2002 Henderson/Lake Mead slot machine rankings.
• Appendix 3E: 2002 Quarter and dollar returns for Las Vegas slots
• Appendix 4 shows how the return is calculated for my Wizard's Fruit Slot Machine.
• Appendix 5 analysis of the 21 Bell Slot Machine.
• Appendix 6 Analysis of Red, White, & Blue Slot Machine.
• Lock and Roll analysis of the skill-based slot machine found in North Carolina.
• Deconstructing Jackpot Party analysis of the video slot machine.
• Deconstructing Lion's Share analysis of the classic MGM progressive game.
• Deconstructing Cleopatra analysis of the popular IGT game.
• Deconstructing Lionfish analysis of the slot game found on many Game Maker machines.
• Deconstructing Megabucks.
• Deconstructing the Atkins Diet slot machine.
• Deconstructing Lucky Larry's Lobstermania.
• Deconstructing Hexbreaker.
• Deconstructing Blazing Sevens.
• Deconstructing Hot Roll.
• Mystery progressives on Ainsworth slots.
• Mystery progressives on WMS slots.
• Baltimore Sun article, in which I am quoted.
• 100% Rebate on Slot Losses Promotions: When to quit playing when all losses are refunded.

External Links

• For a simplified explanation of slots, please see my companion site Wizard of Vegas
• German translation of this page is available at richtigspielen.com
• Another decent overview of how slots work and some practical advice for playing them is How Slot Machines Work at VegasClick.com.
• PAR Sheets, probabilities, and slot machine play: Implications for problem and non-problem gambling by Kevin A. Harrigan and Mike Dixon, University of Waterloo, Waterloo, Ontario, Canada. This is an outstanding academic paper that details how some popular slot machines were designed.
• PAR Sheets, probabilities, and slot machine play: Implications for problem and non-problem gambling - Academic paper based on the par sheets for some modern slot machines

Online casino slots have become enormously popular over the years, and much of their success can be attributed to their simple gameplay. To play, all you need to do is pull the lever (or push the 'Spin' button) to set the reels in motion. Game icons are fixated onto the reels, which spin their way to new combinations with each play. If you see matching icons lined up in a row, you win a payout—that's if you play online slots for real money.

This is the most basic explanation of how slot games work, but in reality, they're more complex than that—especially since they've transitioned to the online realm, where there are endless possibilities to enhance gameplay with innovative new formats. In order to help you better understand how online slots games work, we've compiled this comprehensive online slots guide, which touches on all the elements you'll find in our slot games, including everything from game symbols to free spins sessions.

Online Slots Symbols

Game symbols are the icons that spin vertically with each round. The goal of the game is to land matching symbols on a payline, and with most online slot games, paylines begin on the first reel. There is always a minimum number of matches needed to trigger a payout, and the more matches you get, the bigger the payout is for each game.

As you play our online casino slot games, you'll notice that there are some game symbols on the reels that act differently than the standard ones. These are your wilds, scatters, bonus icons and multipliers; each one benefits you in unique ways.

Wilds

A wild symbol can transform into any of the standard game icons in order to complete a winning line. For example, if you land Q-Wild-Q on a payline, the wild becomes a Q and you get paid for landing three Qs. Some wilds have additional capabilities, such as expanding wilds which can run up and down the entire reel, and sticky wilds, which trigger a free re-spin while staying in place.

Scatters

Normally, game icons must land side by side in order to trigger payouts, but scatter symbols are an exception to this rule. They can land anywhere on the reels and still trigger a bonus, such as a free spins session, a cash payout or bonus round.

When it comes to gambling, the easier a game is to understand the worse the odds usually are. This is certainly the case with slot machines. Playing them is as easy as pressing a button. However, between the high house edge and fast rate of play, there is no quicker way to lose your money in a casino.

Before going further, let me make clear that this page addresses the way slot machines work in most parts of the United States and the world. However, some parts of this page do not apply everywhere. For example, I state that slot machines have a memory-less property, where the odds of every spin are the same. In some places, like the UK, some machines in bars, called 'fruit machines,' have a mechanism that guarantees a certain profit over the short run, which causes the game to go through loose and tight cycles. These games do not have the usual independence property of the major slot makers.

How They Work

Whether you're playing a 3-reel single-line game or a 5-reel 25-line game, the outcome of every bet is ultimately determined by random numbers. The game will choose one random number for each reel, map that number onto a position on the reel, stop the reel in the appointed place, and score whatever the outcome is. In other words, the outcome is predestined the moment you press the button; the rest is just for show. There are no hot and cold cycles; your odds are the same for every spin on a given machine.

Slot machines are just about the only game in the casino where the odds are not quantifiable. In other words, the player doesn't know how the game was designed, so it is difficult to look at an actual game to use as an example. So, to help explain how they work, I created the Atkins Diet slot machine (link). It is a simple, five-reel game with a free spin bonus round, much like IGT's Cleopatra game.

For information on how it works and all the odds, please visit my Atkins Diet par sheet.

For a more complicated example, featuring sticky wilds in the bonus, please try my Vamos a Las Vegas slot machine.

For information on how it works and all the odds, please visit my Vamos a Las Vegas par sheet (PDF).

Odds

The following table shows the casino win for Clark County Nevada (where Las Vegas is) for all slots for calendar year 2012. They define 'slot' as any electronic game, including video poker and video keno. I've found video keno to be about equally as tight as reeled slots, but video poker has a much higher return. So, the return for reeled slots should be higher than these figures.

Clark County Slot Win 2012

Source: Nevada Gaming Control Board, Gaming Revenue Report for December 2012 (PDF, see page 6).

Most players play penny video slots. Based on past research, I find the house edge on those to usually be set from 6% to 15%. In general, the nicer the casino, the tighter the slots.

Advice

While there is no skill to playing slots, there is some skill in selecting which machine to play and ways you can maximize your return. What follows is my advice, if you must play slots at all.

• Always use a player card. Slots may be a lousy bet, but the casinos treat slot players very well. A $1 slot player will probably get comped better than a $100 blackjack player. Of course, don't play for the reason of getting comps. You'll give them a lot more than they'll give you.
• The simpler the game, the better the odds. The fancy games with big signs and video screens tend to not pay as well as the simple games. However, slot players always tell me the fancy games are more fun.
• The higher the denomination, the better the odds. For that reason, it is better to play one coin per line on a 5-cent game than five coins per line on a 1-cent game.
• Don't forget to cash out and take your ticket when you leave. It is easy to forget after hitting a jackpot.
• Try to play slowly and as little as possible to get your fix.
• In some games there is a skill feature, like Top Dollar. In such games, advice is usually offered, which you should take.

Myths and Facts

Just about everything that players believe about slots is untrue. Here are the most common myths and facts. As a reminder, this page is based on slot machines commonly found in the United States. Some machines, like 'fruit machines' found in the United Kingdom work differently.

• Myth: Slot machines are programmed to go through a cycle of payoffs. Although the cycle can span thousands of spins, once it reaches the end the outcomes will repeat themselves in exactly the same order as the last cycle.

  Fact: This is not true at all. Every spin is random and independent of all past spins.

• Myth: Slot machines are programmed to pay off a particular percentage of money bet. Thus, after a jackpot is hit the machine will tighten up to get back in balance. On the other hand, when a jackpot has not been hit for a long time it is overdue and more likely to hit.

  Fact: As just mentioned, each spin is independent of all past spins. That means that for a given machine game, the odds are always the same. It makes no difference when the last jackpot was hit or how much the game paid out in the last hour, day, week, or any period of time.

• Myth: Machines pay more if a player card is not used.

  Fact: The mechanism that determines the outcome of each play does not consider whether a card is used or not. The odds are the same with or without one.

• Myth: Using a player card enables the casino to report my winnings to the IRS.

  Fact: That makes no difference. If you win $1,200 or more they will report it either way. If you have a net losing year, which you probably will, at least the casino will have evidence of it. Such annual win/loss statements may be used as evidence to declare offsetting loses to jackpot wins.

• Myth: The slot department can tighten my game with the press of a button remotely. Thus, you better be nice to the staff and tip them well, or they will use a remote control to have the machine take you down in a hurry.

  Fact: There is now some truth to the myth that the odds of a machine can be changed remotely. Such 'server-based slots' are still experimental and in a minority. Even with server-based slots, there are regulations in place to protect the player from the perceived abuses that could accompany them. For example, in Nevada a machine can not be altered remotely unless it has been idle for at least four minutes. Even then, the game will display a notice that it is being serviced during such changes. (source) Meanwhile, for the vast majority of slots, somebody would physically need to open the machine and change a computer chip, known as an EPROM chip, to make any changes.

• Myth: The machines by the doors and heavy traffic flow areas tend to be loose while those hidden in quiet corners tend to be tight.

  Fact: I've studied the relationship between slot placement and return and found no correlation. Every slot director I've asked about this laughs it off as just another player myth.

• Myth: Slots tend to be looser during slow hours on slow days of the week. However, when the casino is busy they tighten them up.

  Fact: Nobody would take the trouble to do this, even if he could. The fact of the matter is the casinos are trying to find a good balance between winning some money while letting the player leave happy. That is best achieved by slots loose enough to give the player a sufficiently long 'time on device,' as they call it in the industry, with a reasonable chance of winning so he will return to the same casino next time. If the slots are too tight, the players will sense it and be unlikely to return.

  The kind of place you're likely to find tight slots are those with a captive audience, like the Las Vegas airport. So, if the slot manager feels that 92% is the right return for a penny game, for example, he is likely to set every penny game all that way, and keep them that way for years.

Play

Reviews

• Dazzle Me (NetEnt)
• Mr. Vegas (Betsoft)
• Sparks (NetEnt)

Internal Links

• Appendix 1 shows the details and analysis of almost 4000 actual spins on a Reno slot machine.
• Appendix 2 shows an example of the virtual reels behind a hypothetical slot machine and how the average return is calculated.
• Appendix 3A: 2003 Las Vegas slot machine rankings.
• Appendix 3B: 2002 Jean/Primm slot machine rankings.
• Appendix 3C: 2002 Tunica slot machine rankings.
• Appendix 3D: 2002 Henderson/Lake Mead slot machine rankings.
• Appendix 3E: 2002 Quarter and dollar returns for Las Vegas slots
• Appendix 4 shows how the return is calculated for my Wizard's Fruit Slot Machine.
• Appendix 5 analysis of the 21 Bell Slot Machine.
• Appendix 6 Analysis of Red, White, & Blue Slot Machine.
• Lock and Roll analysis of the skill-based slot machine found in North Carolina.
• Deconstructing Jackpot Party analysis of the video slot machine.
• Deconstructing Lion's Share analysis of the classic MGM progressive game.
• Deconstructing Cleopatra analysis of the popular IGT game.
• Deconstructing Lionfish analysis of the slot game found on many Game Maker machines.
• Deconstructing Megabucks.
• Deconstructing the Atkins Diet slot machine.
• Deconstructing Lucky Larry's Lobstermania.
• Deconstructing Hexbreaker.
• Deconstructing Blazing Sevens.
• Deconstructing Hot Roll.
• Mystery progressives on Ainsworth slots.
• Mystery progressives on WMS slots.
• Baltimore Sun article, in which I am quoted.
• 100% Rebate on Slot Losses Promotions: When to quit playing when all losses are refunded.

External Links

• For a simplified explanation of slots, please see my companion site Wizard of Vegas
• German translation of this page is available at richtigspielen.com
• Another decent overview of how slots work and some practical advice for playing them is How Slot Machines Work at VegasClick.com.
• PAR Sheets, probabilities, and slot machine play: Implications for problem and non-problem gambling by Kevin A. Harrigan and Mike Dixon, University of Waterloo, Waterloo, Ontario, Canada. This is an outstanding academic paper that details how some popular slot machines were designed.
• PAR Sheets, probabilities, and slot machine play: Implications for problem and non-problem gambling - Academic paper based on the par sheets for some modern slot machines

Online casino slots have become enormously popular over the years, and much of their success can be attributed to their simple gameplay. To play, all you need to do is pull the lever (or push the 'Spin' button) to set the reels in motion. Game icons are fixated onto the reels, which spin their way to new combinations with each play. If you see matching icons lined up in a row, you win a payout—that's if you play online slots for real money.

This is the most basic explanation of how slot games work, but in reality, they're more complex than that—especially since they've transitioned to the online realm, where there are endless possibilities to enhance gameplay with innovative new formats. In order to help you better understand how online slots games work, we've compiled this comprehensive online slots guide, which touches on all the elements you'll find in our slot games, including everything from game symbols to free spins sessions.

Online Slots Symbols

Game symbols are the icons that spin vertically with each round. The goal of the game is to land matching symbols on a payline, and with most online slot games, paylines begin on the first reel. There is always a minimum number of matches needed to trigger a payout, and the more matches you get, the bigger the payout is for each game.

As you play our online casino slot games, you'll notice that there are some game symbols on the reels that act differently than the standard ones. These are your wilds, scatters, bonus icons and multipliers; each one benefits you in unique ways.

Wilds

A wild symbol can transform into any of the standard game icons in order to complete a winning line. For example, if you land Q-Wild-Q on a payline, the wild becomes a Q and you get paid for landing three Qs. Some wilds have additional capabilities, such as expanding wilds which can run up and down the entire reel, and sticky wilds, which trigger a free re-spin while staying in place.

Scatters

Normally, game icons must land side by side in order to trigger payouts, but scatter symbols are an exception to this rule. They can land anywhere on the reels and still trigger a bonus, such as a free spins session, a cash payout or bonus round.

Bonuses

With some online slot games, only scatters trigger the bonuses. But with other slot games, there are additional bonus symbols, which award something extra, like a cash prize or bonus round. For an example of a slot game that has both scatters and a bonus, check out Animal Wilds slot.

Multipliers

Why settle for a standard payout when you can multiply that payout by three times, five times, or even more? Multipliers significantly boost your return by multiplying payouts by the number shown in the symbol.

Paylines

For the majority of slot games, matching icons can't just land anywhere—they must land on a payline in order to be considered a win. These invisible lines go from the first reel to the last reel in various orders. The most basic payline is a simple horizontal line that goes left to right.

Paylines have a direct impact on win frequency, as having more paylines included in a slot game increases the odds of landing matching icons on them. That being said, you pay for each payline, so the cost per spin increases with the number of paylines included by players.

Betting Level

Your bankroll will dictate what kind of real money slots games you can play as well as the betting levels for them. While some slots simply ask you to choose how much money you want to bet per round, others let you pick the number of coins you want to wager per payline and the coin denomination, creating a more custom experience.

Let's take Catsino slot for example. In this 5-reel, 50-line slot, you can wager up to 10 coins per payline, and your coin denominations include: $0.01, $0.05, $0.10, and $0.25. That means, you can wager a minimum of one penny per line for $0.50 rounds, and a maximum of 10 quarters per line for $125 rounds.

Understanding Casino Slot Machines Book

Another way you can alter your betting level is through the 'Select Lines' button, which lets you choose how many paylines to activate. Just be mindful, when you start playing with just a handful of paylines, certain bonus features (expanding wilds, for example) lose their benefits. You should also be aware that certain jackpots are only available when betting the maximum number of coins. Simply check the game's paytable to see what betting minimums are required.

Progressive Jackpots

Most slot players dream of triggering progressive jackpots. These are the massive payouts that are funded by a percentage of incoming bets placed on the game. You'll see them advertised in the tens of thousands at the top of the game screen.

There are a few different ways to trigger a progressive jackpot. We'll cover each one, but it's important to read the rules of the game before starting in order to ensure you know exactly what's required to be eligible.

Random Progressive Jackpot: Some slots include Random Progressive Jackpots, which means the award is given out randomly at the end of any given spin. A Night With Cleo is an example of a slot game with a random progressive jackpot.

Top Line Progressive Jackpot: These jackpots are offered as payouts for winning the top combination of a game. Strike Gold is an example of a slot game with a Top Line Progressive Jackpot.

Bonus Feature Progressive Jackpot: Newer slot games are starting to include progressive jackpots as awards triggered through a bonus feature. Gold Rush Gus has one of these jackpots; it's one of the four rewards given out through the Treasure Chest Bonus.

Bonus Round

A bonus round takes you to a new screen, where you get an opportunity to boost your bankroll by completing a challenge. The challenge coincides with the theme of the game, making the experience more engaging and interactive than simply spinning the reels. Robin Hood slot, for example, has a bonus round called Marian's Prize, where you attempt to locate Robin Hood's Merry Men behind 'Wanted' posters. The more times you're able to do this without uncovering the Sheriff of Nottingham, the more money you end up with.

Understanding Casino Slot Machines Game

Free Spins

Understanding Casino Slot Machines -

Free spins let you spin the reels and collect payouts without having to stake any of your bankroll. These are often triggered by landing scatters, and the more scatters you land, the more free spins you get. One of the best online slot games tips out there is to thoroughly examine the free spin situation, as free spins with multipliers—that can also be retriggered—are the most valuable free spins out there.

Some new slots are getting creative with their free spins. With Gold Rush Gus, there are two ways to get free spins: one is through landing scatters and another is through a no-win outcome. The free spins triggered by scatters come with a 2X, 3X or 4X multiplier.

With the exception of progressive jackpots, these basic elements are included in mostreal money slots online. Knowing how slot games work not only gives you a better understanding of slots in general, but also provides insight on how valuable a game is based on its bonus features. Browse our slot selection and see how many bonus features you can get in a single game for the full online slot games experience.