Roulette Odds & Probabilities
There are generally two well known types of Roulette played in casinos and online around the globe.
American Roulette
The American Roulette Wheel has 38 numbers including 0, 00 and numbers 1 to 36. As the house normally only pays 35 times the stake (plus the stake) on a straight bet, this means it always has a two number advantage over players. In other words if a player or players covered all of the numbers on the board it would cost them say $38 (i.e. $1 per number), however the house’s maximum payout will only be $36, hence they always have 2 number advantage on the players. 2/38 = 5.26% advantage. Having two zeros (0, 00) gives the house a 5.26% advantage. This means that for every $100 bet, the house will make $5.26 in profit. Be aware, there is also “Five Number Bet” which gives the casino a 7.89% edge. The betting numbers are 0, 00, 1, 2, 3 at the same time. It is the worst bet in roulette, NEVER ever make “five number bet”.
European Roulette Wheel
The European Roulette Wheel, also referred to as the ‘French Wheel’ has 37 numbers including 0 and 1 to 36. As the house normally only 35 times the stake (plus the stake) on a straight bet, this means it always has a one number advantage over players. In other words if a player or players covered all of the numbers on the board it would cost them say $37 (i.e. $1 per number), however the house’s maximum payout will only be $36, hence they always have 1 number advantage on the players. 1/37 = 2.70% advantage. Having one zero (0) on the wheel gives the house a 2.70% advantage. This means that for every $100 bet, the house will make $2.70 in profit.
Naturally, wherever possible we recommend players play European Roulette due to the better odds.
Below we list the mathematical probability of a win for each type of roulette bet on both American and European Roulette wheels. Full descriptions of each bet type are available on our Roulette Bets & Payout page.
| Bet Type | American Roulette | European Roulette | ||
| Probability | . % | Probability | . % | |
| Straight Bet (1 number) |
1/38 | 2.63 | 1/37 | 2.70 |
| Split Bet (2 numbers) |
2/38 | 5.26 | 2/37 | 5.41 |
| Street, Trio Bet (3 numbers) |
3/38 | 7.89 | 3/37 | 8.11 |
| Corner, Square (4 numbers) |
4/38 | 10.52 | 4/37 | 10.81 |
| 5 Number Bet |
5/38 | 13.16 | 5/37 | 13.51 |
| Line Bet (6 numbers) |
6/38 | 15.79 | 6/37 | 16.22 |
| Column Bet (12 numbers) |
12/38 | 31.58 | 12/37 | 32.43 |
| Dozen Bet (12 numbers) |
12/38 | 31.58 | 12/37 | 32.43 |
| Odd / Even Bet (18 numbers) |
18/38 | 47.37 | 18/37 | 48.65 |
| High / Low Bet (18 numbers) |
18/38 | 47.37 | 18/37 | 48.65 |
| Red or Black Bet (18 numbers) |
18/38 | 47.37 | 18/37 | 48.65 |
Multi Spin Bets - Roulette Probability Calculations :
The table above can be very useful in calculating the odds for all types
of bets. As an example. let’s say you wanted to calculate the mathematical probability of winning with the same bet on a Dozen over say 3 spins.
STEP 1 : The chance of winning on a dozen bet in one spin is 31.58% or 0.3158
STEP 2 : The chance of LOSING on a dozen bet in one spin is therefore 100% - 31.58% = 68.42% (0.6842)
STEP 3 : To Calculate the chance of LOSING over three spins, multiply the Losing percentage on one spin 3 times. So this is 0.6842 X 0.6842 X 0.6842 = 0.3203 OR 32.03% Chance of LOSING over 3 SPINS
STEP 4 : Therefore the Mathematical Probability of WINNING over 3 spins is 100% - 32.03 % = 67.97% CHANCE that you will WIN placing a bet on a Dozen bet in 3 SPINS.
