How Casino Games Work

Poker Hand in Front of Metal Gears

Everyone knows how casino games work, don’t they?

Actually, you’d be surprised. I’ve heard some of the most insane strategies and ideas about how to go about playing real money casino games.

The purpose of this post is to explain how casino games work so that maybe there’ll be less misinformation about it in the future.

This is ideal for those who don’t yet know much about gambling and are looking to learn more about how most casino games work.

Math Is a Critical Part of Understanding Casino Games

Some people think that casinos and real money online casinos make money from their games because they cheat. That’s not at all true. Casinos don’t have to cheat, because they use the math of larger numbers to guarantee themselves a profit.

Here’s how that works.

Every casino game has payout odds, which is the amount you get paid if you win the bet compared to the amount you had to risk.

Chalkboard With a Variety of Math Problems

Many games have even odds where, if you bet $100 and win, you get $100 in winnings. Other games might pay off at 2 to 1 or 3 to 1 if some conditions are met. If you bet $100 and win, you’ll get $200 or $300 given those odds.

The thing about these bets is that you can also use odds to describe the probability of winning.

For example, if something is going to happen half the time, the odds are even, or 50/50.

If something is only going to happen 46% of the time, and the bet pays off at even money, someone is going to profit in the long run. And someone else is going to lose in the long run.

Guess who’s going to win 54% of the time on a casino game? That’s right. It’s the casino.

More About Odds and Probabilities Related to Casino Games

Let’s look at a really clear, specific example of how this works in reality in the game of roulette.

A real money roulette wheel has 38 numbers on it, and you can place a bet on which number the ball will land in. If you bet on the right number, you get a 35 to 1 payout.

Now, suppose you have a table full of gamblers, and each person picks one number and bets $100 on it. Or suppose that one player decides he absolutely MUST win, so he bets on all 38 numbers.

What’s the outcome for the casino? They win 37 of the 38 bets, for $100 each, so they win $3,700. They lose one of those bets, and they pay out $3500 on the winning bet. This leaves them with a $200 profit.

If you average that $200 profit by all 38 bets, you’ll get $5.26 per bet on average. And that’s how the casino makes its money, by paying out at odds lower than the odds of winning.

How Slot Machines Work

Of course, most people don’t play table games like blackjack, craps, or roulette anymore. 80% of most casino revenue comes from the slots.

How do the slot machines work? As it turns out, they work almost exactly like the table games. The major differences are the bigger payouts for the top jackpots and the correspondingly lower odds of winning them.

Also, on a gambling machine, your payout is done on an “x for y” basis rather than an “x to y” basis… What does that mean?

Well, it means that you don’t get to keep your original bet in addition to your winnings. You’re trading your original bet for what you’ve won.

Closeup of Three Reel Slot Machine

This means that if you win an even money payout on a slot machine, you’re not actually winning anything. You just didn’t lose any money. In a table game, that would be considered a “push,” which is a fancy casino term for “tie.”

Let’s say you have 2,000 different possible outcomes on a slot machine. Then, let’s say you have 1,800 possible payouts on all the winning combinations.

That slot machine game would have a 90% payback ratio, which is the amount that the slot machine pays back on average on every spin. It’s like paying a 10% tax on every bet.

Are Casino Games Random?

I read a lot of blog posts from an author who likes to point out that most casino game outcomes aren’t TRULY random, but they’re close enough. They’re confused about what random means.

Random just means that the outcome isn’t predictable. You might have a biased roulette wheel, for example. Some numbers might come up slightly more often than others. This doesn’t mean the game isn’t random.

It’s still random, but the odds are just tilted away from what they should be.

Casinos don’t have an incentive to have a non-random roulette game with a biased wheel, though. If they did have one, they’d be putting themselves in a position where savvy players could figure out the bias and profit from it.

They make MORE money offering random games than they would if they had games that were predictable.

That’s an important thing to understand about how casino games work. The casinos are incentivized to make sure they’re random and fair. If they weren’t random or fair, the casino would make less money.

What Are the Different Types of Casino Games?

Casino games can be broadly categorized into three types:

  1. Gambling machines
  2. Novelty games
  3. Table games

Gambling machines are currently the most popular type of casino game in the United States. Slot machines are an example, and video poker is the second most popular example. But you can also find video blackjack and video roulette games.

Novelty games include games like keno and other “carnival style” games. These games tend to have a higher mathematical advantage for the house than gambling machines or table games.

Table games are the games you see played at the various tables in the casino. The most popular of these include baccarat, blackjack, craps, and roulette.

The table games tend to have the lowest mathematical advantage for the house. The most notable exception is video poker, which often has a lower edge than blackjack.

The problem is that you have to be familiar enough with the pay tables for the variations of video poker to spot the ones with the higher payback percentages.

With most table games, you can bet a low house edge by just sticking with the best bets at the table. And at some tables, all the bets carry the same mathematical edge.

Which Casino Games Are Best?

The best casino games to play are the ones you enjoy the most. That advice runs counter to what you’ll read on many sites.

Most books and websites advise you to stick with the games with the lowest edge, but I disagree with this advice.

Imagine this. Suppose you’re playing blackjack for an hour, and you’re pretty sure that you’re going to lose $10 per hour while you’re playing. Let’s also suppose you HATE playing blackjack.

On the other hand, you’re playing slots for an hour, and you’re pretty sure you’re going to lose $50 per hour while you’re playing. Let’s also suppose you LOVE playing slot machines. Which game should you play?

At the end of the day, if you play casino games, you’re going to lose all your money if you play long enough. That’s just how the math behind the game works.

So, even if you’re going to lose your money faster on a game with a high house edge, if it’s more fun, that’s the game you should play.

How Can I Win More Often Playing Casino Games?

In the long run, you can’t win unless you’re some kind of advantage player. Learning how to beat the casinos in the long run is beyond the scope of this post.

But, in the short term, the nature of random chance means you’ll sometimes win. I’d estimate that 20% of the time, you should be able to walk away from the casino with some winnings in your pockets.

Your goal should be to increase your likelihood of getting into the winnings in the short run. That’s easier to do than you think.

Start by playing games with the lowest house edge. This means playing blackjack and learning the correct basic strategy for the game. It also means learning about the pay tables in video poker and learning how to play that game with the correct mathematical strategy.

Craps is another game where you can get a low house edge, but you have to stick with the best bets at the table. At some games, like roulette, almost all the bets have the same house edge. But, in craps, many of the bets have a really big advantage for the casino. Avoid those bets.

The best way to increase your odds of walking away from the casino a winner is to stay far away from the slot machines. They have the worst odds of winning, except for maybe keno.


That’s the basic idea of how casino games work and what you need to do to get the most out of them.

What questions do you have about casino games now? Post them in the comments, and I’ll try to answer those questions.