Roulette Odds Calculator

Detailed Explanation of Roulette Odds & Probabilities

Many hardcore roulette players insist that you need to be skilled at playing roulette, but the reality is that it all comes down to luck. But at its core, roulette is a game of probabilities and odds. Every time you place a bet at the roulette table, you should be aware that the probabilities of winning are not the same for all bets, and they will also not be the same on all variants. We also need to be clear that the odds and probability terms are not the same. This is why, in the following sections, we differentiate and explain them, as well as help you understand and calculate the probabilities and odds for each type of roulette bet.

Odds and Probabilities Chart of Roulette Bets

We already mentioned that the odds and probabilities on each bet, as well as each version of roulette, are not the same. To make your life easier, we already have a table ready where you can check the values of each bet. We will also explain in detail how to understand each of the values from the table.

You can clearly notice that the probabilities differ from one roulette variant to another. If we compare the European and American variants, we notice that the European variant with a single zero has higher win probabilities. This difference isn’t noticeable on straight bets, with a 0.1% deviation, but it increases when you cover more numbers. Once you move to bets with even money, which covers 18 total numbers, the value spikes up to 1.2%.

NOTE! We simply use the two terms to show you two different ways of determining the chance of a win landing.

• The probability is shown in percentage and refers to the probability of winning a specific bet.
• Odds refer to the probability ratio for winning or losing the bet.

How Works Roulette Odds and Probabilities Calculator?

If you want to know how to get the probability for a bet to land, have no fear. It’s actually very easy and simple. You simply take the amount of numbers from the bet you used and divide it by the total number of numbers on the table. After that, multiply that number by 100. Here’s what it looks like in real-life examples.

• The European Roulette variant has a total of 37 numbers, ranging from 0 to 36.
• For a straight bet, where you bet on one number, you use the equation 1/37*100.
• The number you get is 1/37 = 0.0270, which is your chance of winning the bet.
• After you multiply that number by 100, the chance comes down to 2.7%.
• Here’s what it would look like if you decide to go with an Even or Odds bet. Since there are 18 numbers in total, the formula for the Even or Odds bet looks like this.

18/37*100 = 48.64% to win

Once we’re done with the probabilities, we move on to the odds. For them, we see how many chances there are for a win and divide them by the number of chances for a loss. Here’s how that works:

• European Roulette comes with 37 numbers in total.
• A single Dozen Bet includes 12 numbers in total.
• So, you can have 25 losing outcomes, 37-12 = 25.
• This means the odds for the dozen bet come down to 12:25.
• According to the odds, any 12 wins come with an average of 25 losses.

All examples we have used so far are from the European roulette variant, meaning they apply to single-zero variants. In case you want to make the calculations on double-zero American roulette, you need to adjust the equations. In the table below, you will see the formulas; simply add the values you need.

• Number of Winning Outcomes - total number of numbers covered
• Number of Losing Outcomes - total number of uncovered numbers

• Total number of numbers = 37 for single-zero roulette
• Total number of numbers = 38 for double zero

How to determine the win probabilities in complex bets

In most cases, you are more likely to use several bets at the roulette table rather than only one. This is why, on complex bets, we need to figure out the probability of it landing. Here’s an example of how that would work. One unit goes to the first dozen, and you choose 5 numbers from the second dozen. You also make three split bets on the third dozen. This is what that would look like:

• You have a total of 37 numbers on the table.
• The first dozen bet is on 12 numbers in total.
• The five straight bets are on 5 numbers.
• The three split bets are on 6 numbers.
• In total, we used 23 numbers: 12 + 5 + 6 = 23.
• Divide the number of covered numbers by the full number of positions on the table: 23/37=0.6216.
• Multiply the result by 100 to get the probability. The result is 62.16% of winning the bet.

If we’re talking about odds, they come out to 23 to 14. This means that every time you hit a total of 23 winning spins, you would also have 14 losing ones.

Note! You should also be aware that with bets like this one, where you combine bets with a low number of positions and bets with a higher number of positions, you determine the odds and probabilities from the maximum number of used numbers. According to the previous example, we used a total of 12 numbers, so the probability is (12/37) x 100 = 32.43%. From that, the odds are 12:25.

Probabilities And Odds For Announced Bets

Some players prefer to play Announced bets, while others call them Called bets. And at some tables, you can find the term French bets. The main detail here is that they come with separate odds. Called French or Announced Bets, regardless of the name they use, come with different odds. Here, you use a multitude of numbers, in some cases as much as half of the total. So, the odds for Tiers du Cylindre will be quite different from the ones on Voisins du Zero. Here’s what it looks like.