Slots are known by different names across the globe, from “fruit machines” in the UK to “pokies” in Australia. But no matter what they’re called, these games remain the leading revenue generators for almost all land-based and online casinos. In this article, we’ll look at how a modern slot works, the leading manufacturers of games, and the always-elusive payback percentage.

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How a Slot Machine Works

There’s one primary element to modern slot machines: the random number generator. As soon as a slot becomes active, this function starts generating random numbers at an inhuman rate (usually hundreds per second).

The instant a player presses the spin button on a slot machine, the random number generator (or “RNG”) grabs the most current series of digits and uses them to determine the outcome. While the spinning symbols present the illusion that the final result is determined one reel at a time, it’s actually over as soon as the player decides to press the button. Of course, slots would lose much of their appeal if the results were instantly displayed.

Even though winning symbols are selected at random, some are programmed to appear more often than others. If this weren’t the case, wild and bonus symbols would turn up at a much higher frequency and result in a major loss for the house.

Despite superstitions to the contrary, slot machines are not programmed to run hot and cold. A game might go 20 years without paying out a progressive jackpot, or it might deliver two of them in the same day. That’s good news for the customer, as it means playing right behind a jackpot winner gives you the same odds of success as they had.

House Edge

The house edge on most slots ranges from 6% to 15%. Land-based slots have to pay out a minimum amount as determined by their state or country, while online games tend to be less regulated. If you stick with a reputable Internet casino that uses software from a leading provider, however, you should be okay.

Odds & Payback %

When it comes to slots games there are so many variations today that figuring out your odds is nearly impossible. Instead, slots game odds are expressed in the form of payback percentages. As a player you want to search for games that give you the biggest payback percentage you can find, and online that should be at least 99% or better.

It’s rumored that brick and mortar casinos will even have loose slots games that pay out at more than 100%. The casinos supposedly place these games in high-profile areas so more patrons can witness someone hitting a big payday. There are none of these loose games online, but the average payback online is greater than the average you’ll find in any regular casino.

For a nickel slots game the average payback percentage in live casino is 92.5%. The quarter machines pay back an average of 94.1%, the dollar machines 95.9%, and the high stakes $5 games pay back 98.4%. Online the overhead is much less than in a live casino, so payback percentages can be bigger without the house feeling the pinch.

Online, most casino slots games’ payback percentage is around 99%. With so many casinos to choose from, and if slots are your thing, you have to take the time to find the best games with the highest paybacks. It may not be a big difference during one session, but over the longer term of playing the game it will add up to a significant amount.

Progressive Jackpots

Progressive jackpots can increase the payback percentages of slots games because the jackpot amount considerably increases the potential win. If the jackpot is big enough, the return on a game can easily exceed 100% of the intake, thus giving the players a positive betting situation.

Just remember, when it comes to progressive jackpots, the bigger they are the better the payback percentage. Wait until the jackpot has grown to a good size before playing, and make sure that you remember to play maximum bet on any progressive jackpot game you play. If you don’t play max bet, you don’t qualify for the jackpot, and your payback percentage will go way down.

Bankroll Management

When it comes to numbers and odds with slots games, bankroll management is the thing to know. These calculations are simple enough to learn, one simply needs to start with figuring out how much money one has to spend on the slots. Once you know how much cash you have to spend then you can divide that up into playing sessions. How often you play a session will be different for every player.

It’s important for players to understand that playing slots online is all about being in the game as long as possible, so playing at the right stakes levels will ensure that you get enough time on the games to have a decent chance at hitting a big payday. All slots games slowly deplete your bankroll until that payday comes, so playing in games where stakes are too big will cause you to use up your bankroll before that big hit shows up.

Each slots game will deplete your bankroll at a different rate. One can expect to lose faster on a slots game that has a higher potential payout. When the potential payout is smaller, like in many three-reel games, that losing rate will be slower. One should balance their stakes with the losing rate to ensure that they have enough money to get through all their planned playing sessions without going broke.

On average, in a slots game with a payout of 90% where a player is taking ten spins per minute, a player will need $9.00 per hour played on a nickel machine, $45.00 per hour on a quarter machine, $180 per hour on a dollar machine, and $900 per hour on a $5 machine. Online payout rates are higher than the above 90%, but one will often play faster online, so these numbers should be good guidelines.

The most common bankroll management strategy mistake that players make is to not get out when they’re ahead. A predetermined amount should be decided upon and a player should get out of the game if their bankroll reaches or exceeds it following a big spin win. Stepping away at the right time is essential to having a winning session or not.

One of the worst things that many players will do following a big spin win is to continue to play just to get their credit total down to a round number. Don’t throw away money just to get an even figure payday. Some players will throw back a considerable amount just to play a little longer on the games.

Slots Strategy

If someone offers to share a slots strategy with you, prepare to be assaulted by poorly-informed nonsense. That’s because there is no system or trick for beating slot machines, and anyone who tells you different is either mistaken or trying to sell you something.

The truth of the matter is that modern slots are equipped with technology known as a random number generator. This ensures that all spins are independent of one another, so it’s impossible to predict what symbols are going to turn up on the reels.

There’s also the payback percentage, a figure that’s programmed into a slot to govern what amount it pays out over the life of the machine. Even if it’s a generous number like 97%, long-term play should still result in a 3% loss.

In this article, we’ll look at some of the most popular slots myths and explain why they’re false. We’ll also identify a couple of questionable individuals who claim to sell slots systems.

Slot Machine Myths

The following are some of the most common myths regarding slot machines. If you want to get the most for your money, you’ll avoid falling prey to these fallacies.

"Always Bet the Maximum"

Some players insist that you must wager the maximum amount, as it gives you a better chance of winning. This is false, as the random number generator does not take the size of the player’s wager into consideration. The only time I suggest risking the maximum is on progressive slots, as the rules usually require such a bet to be eligible for the jackpot.

"Use Hot or Cold Coins"

The temperature of your coin has nothing to do with wins or losses, and you’ll just end up looking ridiculous if you fall for this one. Even if this were true, it wouldn’t help online slots players.

"Patterns Can Be Predicted"

There’s no way to tell which symbols are going to turn up on a modern slot. The RNG assures this with the precision of a computer.

"Slot Systems Work"

A slot system is supposed to be a method of play that allows you to beat slots on a consistent basis. Sold by men such as Bill Stone and John Patrick, these systems are inherently flawed. Of course, only the desperate would do business with people who also promise to show you the secrets of beating the lottery or finding evidence of sorcery. 

A notable example is the Zig Zag System. Sold online for actual money, this not-so-brilliant system encourages players to walk the casino floor looking for slots with winning symbols that are just slightly out of alignment. The idea if that the icons should align within a few more spins, but the random number generator makes this a laughable premise. 

I also advise staying far away from the Martingale, a betting system that’s been costing players money for decades. The idea behind this system is that a player should always double their bet after a loss. When you eventually win, this is meant to cancel out all the losses you incurred along the way. In reality, it’s a good way to go broke and cause your gaming session to end on a sour note.

"Single Coin Bets"

Some superstitious players believe that you’re more likely to win by betting a single coin. As I mentioned earlier in this article, the random number generator determines the winning symbols on the reels and it doesn’t care about how many coins you just pumped into the machine.

"A Machine is Due to Hit"

Just because a slot machine hasn’t paid out in a while, players become convinced that the next spin is going to make up for the dry spell. While slots are programmed to give back a certain percentage of winnings, this is calculated over a near infinite number of spins.

"Casinos Can Instantly Adjust a Slot"

This paranoid belief centers around the idea that the casino can make a machine looser or tighter at will. While machines can be adjusted, this isn’t something that’s done on the spur of the moment to shut down a player on a hot streak. 

"Slots Pay in Cycles"

This myth claims that slots go through a cycle of payouts. Once that cycle has run its course, it starts over from the beginning. The idea, of course, is to observe the machine and memorize the pay cycle. As usual, the RNG makes this a ludicrous idea and a waste of time.

Now that you’ve finished reading, I hope you realize that any form of slots strategy is doomed to fail in the long run. Even if you manage to enjoy some initial success, it’s nothing more than dumb luck at work, and the casino payback percentage is bound to shift the odds in favor of the house.  Armed with this knowledge, the best course of action is to concentrate on having fun.

Types of Slot Machines

The types or slot machines available at online and land-based casinos are more varied than most players would initially assume. That’s because gaming establishments are always searching for new ways to draw in customers, just the same way that an auto manufacturer looks for new wrinkles to make their products appealing.

Keep in mind that a large number of slots fall into multiple categories, such as a multi-line slot that offers bonus rounds and a progressive jackpot. I enjoy these options the most, as there’s always something to keep the player’s attention. Some casino clients, however, like games that are more straightforward and less complicated. That’s the great thing about variety, as it provides those with differing tastes the opportunity to find the machine that’s perfect for them. 

Reel Slots

Only found in land-based casinos, these were the original slot machines that used physical reels instead of video displays. No new versions of this type are produced, although they’re still valued by some collectors.

Video Slots

The modern form of slot machine, this type of game computer technology to display virtual reels. It’s not uncommon for them to also include animation and clips from popular movies or television shows.

Straight Slots

The most basic version of the modern slot, this type of game awards prizes as determined by the pay table. In addition to normal wins, these games often feature scatter symbols, multipliers, wild symbols, and even bonus rounds.


The most basic type of slot, this machine offers a single payline across the reels. While this option can still be found, it’s becoming increasingly uncommon. Much of this is due to the fact that modern slots all feature virtual reels, so making 30 paylines doesn’t cost that much more than creating one.


Instead of a single line that pays from left to right, this popular option offers numerous paylines that stretch out in all manner of bizarre patterns on the reels. Just hitting one still results in a win, but it’s possible to win multiple times on a single spin. These have become the industry standard, and the 30-payline game is the most common. There are 50-paylines games, though, and I’ve also seen machines that paid right to left.


When the reels have stopped spinning on this version of the game, the player may choose to spin again while holding one or more reels (usually those containing symbols with the largest payouts). Since the odds of getting a winning combination are increased with this option, the payouts are almost always set at a lower amount.


While certain combinations of symbols offer a set amount, there’ also a top prize that can be obtained. This is known as the “jackpot,” and it offers the largest of the game’s available payouts. This amount is often a fixed number, although the size of your wager can result in a potential increase. 


Each time someone plays a progressive slot, a small percentage of their wager is allocated to the progressive jackpot. That means the prize continues to grow, and it doesn’t stop until the winning combination has been hit. Once that happens, the payout resets to a minimum amount and begin to build again. It’s not unusual to see a progressive jackpot offering a six-figure payout, and some may even climb into the millions.


Instead of just accepting a single denomination, this type of slot machine allows player to select how much they want to wager. This amount could be as low as a penny, or it might climb as high as several hundred dollars.

Bonus Round

If the necessary symbols appear on the reels, a bonus round is unlocked. In some cases, this is as simple as free spins with one or two of the reels displaying different icons. In other cases, the bonus round may unlock animated games that offer free spins or bonus amounts of money. I’ve even seen games where you had to unlock the bonus round before you could be eligible for the progressive jackpot.

Buy a Pay

This type of slot includes multiple payout tables. Higher wagers make you eligible for better payouts, and the maximum amount must be risked in order to have a chance at the jackpot.

Loose and Tight Slots

These aren’t actual types of slots, but players often use these terms to describe different games. A loose slot offers frequent payouts, while a tight slot is stingy when it comes to awarding money to customers.

No matter where you choose to do your gaming, most of the types of slot machines included on this list are bound to be available. The best strategy is to find the game that works best for you, whether it has to do with the payout potential or some other factor, and stick with it. Before you settle on one type, however, there’s nothing wrong with sampling all the available options.

Leading Slot Machine Makers

If you’ve ever played a slot machine, there’s a strong chance that one of the companies listed below was responsible for making it.


BetSoft slots are designed and released by Betsoft Gaming Ltd., an online casino software developer based in the Soho district of London, England. Best known for their line of innovate 3D slots, this company is often cited as being on the cutting edge of the video slot industry.Learn More about BetSoft


Responsible for one of the largest online payouts in Internet history, this virtual gaming manufacturer provides software for 32Red, Ladbrokes, and numerous others.
Learn More about MicroGaming


NetEnt slots are created by Net Entertainment, a Scandinavia-based company that first made its name in the land-based casino business. While the online company was created in 1996, their actual roots within the gaming industry go back much further.
Learn More about NetEnt

RealTime Gaming

Founded in 1998 and including clients such as Bovada, this online casino company is known for their progressive slots, many of which are connected across all casinos powered by RTG.
Learn More about RTG


Rival slots, as well as the other casino games from this online software provider, made their debut in April of 2006. While the selection was limited to begin with, the company has since grown to offer over 160 games for both desktop and mobile gamblers.
Learn More about Rival

History of Slots

If you’re curious about slots history, then you’ve come to the right place. This article was created for the sole purpose of informing readers about the origin of slot machines, and we hope that it provides an interesting look at the development of the game over the decades.

The Creation of Slots

The term “slot machine” originally applied to a number of creations, from 19th gambling devises to automatic vending machines. That all changed in 1898, however, when a Bavarian immigrant in San Francisco named Charles Fey created the first version of the modern-day slot.

Known as the Card Bell, this machine included three mechanical reels, an automatic payout design, and staggered stops. This version of the game included symbols taken from playing cards. The following year, Fey would replace these painted-on symbols with a more patriotic theme including stars and a depiction of the Liberty Bell.

The game was renamed for the cracked American icon, and getting three of these symbols across the reels would result in the top payout of 10 nickels. Once his invention was in working order, Fey started renting them to bars in exchange for 50% of the machine’s profits.

Fey was a prolific inventor during this period. In addition to the first real slot machine, he also created the first Draw Poker game. Other devices have been forgotten by all except historians and include names such as Klondike, Three Spindle, 4-11-44, and Horseshoe.

From 1958 until 2006, Fey’s grandchildren Marshall and Frank lived in Reno, Nevada and operated the Liberty Belle Saloon and Restaurant. Their grandfather’s inventions were on display in the building’s upstairs museum, along with numerous other vintage slots and pieces of casino history. Once the business closed, the Liberty Bell machines were relocated to the Nevada State Museum in Carson City.

Increased Competition

Fey did a tremendous amount of business with his slot machine innovation, and it was lucrative enough that multiple companies tried to buy the distribution or manufacturing rights. When Fey refused to sell, they were forced to look elsewhere.

In this case, “elsewhere” was Chicago, Illinois, the home of game manufacturer Hebert Mills. In 1907, he created a machine similar to the Liberty Bell and dubbed it the Operator Bell. It worked in much the same fashion, although it’s notable as being the first slot machine to include fruit symbols such as cherries and lemons.

An increasing number of “Bell” machines began to pop up in saloons across the United States. While the most desirable prize was money, some machines got around local laws against gambling by offering everything from cigars to free food.

Electronic Slots Origin

The potential for electronic games had been demonstrated as early as 1940, but it wasn’t until 1963 that Bally unveiled the first electronic slot machine. Known as “Money Honey,” this game featured an automatic payout up to 500 coins, as well as a bottomless hopper.

This type of game was immediately popular, and they soon began to replace their mechanical counterparts. With a few decades, the classic lever on the side of machines had largely been replaced by a series of front-mounted buttons.

Creation of Video Slots

1976 saw the slot machine industry once again take a major leap forward, as this was when the first video slot made its debut. Developed with the help of the Fortune Coin Company, this machine replaced physical reels in favor of virtual images and internal computer technology.

The game was initially tested in the Las Vegas Hilton and soon received approval from the Nevada State Gaming Commission. From there, it spread to other gaming destinations in the United States. Today, almost all slot machines in operation around the world fall into this category.

First Progressive Slot Machine

Progressive slots offer the opportunity for huge wins, as a percentage of each wager is added to an ever-expanding jackpot. The first game of this type was known as “Megabucks,” and it debuted in 1986 after being created by International Game Technology (IGT).

The Internet Age

In 1994, Microgaming Software became the first developer to create an online casino. This virtual milestone opened the floodgates for the market, and it wasn’t long before companies such as Cryptologic, IGT, Playtech, and Betsoft were also getting in on the action.

While the earliest online slots had crude sound effects and graphics, they made major strides in the following decades. This led to the creation of i-Slots, next generation machines that feature superior audio and state-of-the-art animation. In another 20 years, we might even have holographic slots to look forward to.

That concludes our look at slots history. I hope you’ve found this trip down memory lane to be both entertaining and informative. While it won’t increase your odds of winning a progressive jackpot, it should demonstrate that future casino classics are just one innovative mind away.