Roulette Probabilities
Calculating the probabilities of a certain outcome at the roulette table is very easy. For example, the American roulette table has 36 regular numbers, a zero and a double zero, adding up to 38 numbers. So, if you are betting on a single number you have a 1/38 chance of winning. In the long run you will win one game for every 38 spins. Remember that this is the long run return - in the short term perhaps you will win several spins, perhaps you will not win a single spin.
The casino has the edge in this game. One win will get you odds 35-1 or 35 units if you bet one. But you will have to play 38 spins/units to win 35 units. That means the house edge on a single number bet on the American wheel with 38 different numbers is 2/38 - or 5.26%.
Here are the probabilities of every possible roulette outcome - you can use them when you place your bets on the roulette table.
| Roulette Bets | Odds/ Pays | Roulette Probability |
|---|---|---|
| Red Number | 1-1 | 46.37% |
| Black Number | 1-1 | 46.37% |
| Even Number | 1-1 | 46.37% |
| Odd Number | 1-1 | 46.37% |
| 1 to 18 | 1-1 | 46.37% |
| 19 to 36 | 1-1 | 46.37% |
| 1 to 12 | 2-1 | 31.58% |
| 13 to 24 | 2-1 | 31.58% |
| 25 to 36 | 2-1 | 31.58% |
| Any one number | 35-1 | 2.63% |
| Two number combination | 17-1 | 5.26% |
| Three number combination | 11-1 | 7.89% |
| Four number combination | 8-1 | 10.53% |
| Six number combination | 5-1 | 15.79% |
| 0, 00, 1, 2, 3 combination | 6-1 | 13.16% |
