5 Slot Machines Math Facts You Need to Know

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Slot Machine Math

Slot machines are the most popular form of casino gambling for many reasons. These machines are also the biggest profit center for casinos, which should tell you everything you need to know about playing them.

Casinos offer many game options that are better for you to play than slot machines, but most gamblers don’t understand why. Here are 5 facts based on math about the slot machines that every slots player needs to know.

After you learn these 5 mathematical facts, you might decide that the slot machines aren’t the best option when you’re in the casino.

1 – Random Number Generator Math

A common mistake made by many slots players is assuming that they recognize patterns and/or can time their spins to profit from the random number generator that runs the machine. The casinos actually want you to believe that you can get a edge this way, because it keeps you playing longer and this means that you lose more money.

Modern real money slot machines are complex machines that are more like computers than anything else. They use random number generators to determine the results
for the machine.

Slot Machines

What you see on the screen when you take a spin is simply a form of entertainment, and doesn’t have anything to do with whether or not you win. The slot machine runs the random number generator program, a result is determined, and then the result is shown on the screen. The result is usually a sequence of reels spinning.

The reason why it’s impossible to see patterns or time your spins is because modern random number generators can cycle through millions of numbers every minute. This means that it’s cycling through thousands of numbers every second. The human mind and body simply can’t react fast enough to find any value in this situation.

2 – Near Miss Danger

Slot machine builders and the casinos want machines that keep gamblers spinning the reels as much as possible. Many different tricks have been developed over the years to make you play more.

One of the worst tricks for slot machine players is when the reels appear to just miss a winning combination. The result is the same as any other losing spin, but psychologically it tries to trick you into getting a little rush thinking about how close you came to winning.

When you play slots games, train yourself to ignore the reels and focus only on the results. You either win or lose, and the reels don’t have anything to do with the result. You learned in the first section that the results are determined first, and then the reels show the results.

Most slots players think the reels determine if they win or not. This makes them more susceptible to what looks like a near miss on the reels. Now that you know how slot machines really work you won’t be fooled again.

3 – Losses Disguised As Wins

Not every slot machine uses this trick, but it’s a smart psychological move from the casino’s side. This trick is commonly called losses disguised as wins. Here’s how it works.

You’re playing a slot machine that has a $2 wager amount. You take a spin and hit a small paying combination, and it pays $1.60.

Your mind registers a win and this releases chemicals that make you want to keep playing. But the problem is that you didn’t really win. You lost 40 cents on the spin.

You need to take a close look at the pay table on every slot machine before you start playing. You need to consider many different things when you choose a slot machine to play, but my personal rule is to never play a machine that ha losses disguised as wins.

Slot machine manufacturers and casinos want the machines to be as addictive as possible. Of course, you never see this published anywhere because gambling addiction is a terrible thing. But the truth is that casinos want as many gambling addicts as possible playing.

One of the min ways to keep gamblers playing longer is to give them the chemical rush when they win. The more you get this rush, the more you want to play.

This is why losses disguised as wins are so devious. They’re a tricky way to use math to make you lose more money.

4 – Progressive Slots Jackpot Math

I don’t usually play slot machines, and I don’t usually recommend playing them to beginning gamblers. But I do play some progressive jackpot slot machines. I play them for much the same reason that I buy a lottery ticket from time to time.

A big progressive jackpot slots win can be enough money to change your life. This is the same as the lottery in many ways. You need to get lucky to win a big jackpot, but it’s worth throwing a few dollars at it sometimes.

Slot machines that have progressive jackpots are the only slots games that have a possibility of offering an edge for gamblers. When a jackpot grows to a large enough amount, the edge can flip from being in the casinos favor to being in your favor.


This sounds like a good thing, but there are two problems with it. The first problem is that it’s hard to find the base house edge or return to player percentage for these slot machines. You need this information to determine how large the jackpot needs to be to flip the odds.

The second issue is that just because the odds are in your favor it doesn’t mean that you’re going to win. In fact, unless you get lucky and hit the jackpot, you’re still going to lose money.

I’m all for taking a long shot at a big slots jackpot from time to time, but don’t waste too much money chasing a big pay day. The odds are against you every time.

5 – Total Bet Amount per Spin

Almost every slots player has taken a seat at a penny slot machine hoping to play for a penny or a few cents per spin and found that they had to risk $1 or more on each spin.

It’s important to bet enough to unlock all of the pay lines and any jackpots, but you need to concentrate on the total wager amount on any slot machine you play. Ignore terms like penny slots and nickel slots, because these are just marketing words and don’t have anything to do with how much it costs to play every spin.

The reason why total wager amount per spin is important is because it’ a big part of how much you bet overall. If you’re wagering $2 per spin and take 500 spins in an hour, you’re risking $1,000 every hour.

If you can determine the return to player percentage or house edge percentage for the slot machine you’re playing, you can quickly figure out how much you can expect to lose playing.

Here are 2 examples.

If the slot machine you’re playing has a return to player percentage of 96% and you’re wagering $1,000 an hour, you can expect to lose $40 every hour you play on average. The way to quickly determine this is to subtract the return to player percentage from 100%. This gives you the house edge. Multiply the house edge of 4% times $1,000 and you get your expected loss of $40.

Sometimes you can find the house edge for a slot machine. When you have the house edge you simply multiply it times the amount wagered. If house edge is 5%, you multiply it times the $1,000 you’re risking. This is an expected loss of $50 every hour.


The slot machines in the casino are a danger to your bankroll. These machines crank out a consistent profit for the casinos, which means that they consistently take money from players.

This doesn’t mean that you should never play slot machines, but you need to be careful about how often you play them and how much you lose when you play.

The 5 mathematical facts about slot machines that you just learned can show you how often you should play and how much you should risk when you do play.

Michael Stevens

Michael Stevens has been researching and writing topics involving the gambling industry for well over a decade now and is considered an expert on all things casino and sports betting. Michael has been writing for GamblingSites.org since early 2016. ...

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