Comprehensive Roulette Probability Tables

Understanding the raw mathematics of roulette is the only way to truly grasp how strategies work. Probability is the foundation of every bet, and knowing the exact odds allows you to make informed decisions rather than guessing.

Outside Bet Probabilities

Outside bets are the safest options on the table. In European Roulette, the probability of hitting a Red/Black, Even/Odd, or High/Low bet is 48.6%. The remaining 2.7% is the house edge created by the single zero. This is why these bets are paid out at 1:1.

Inside Bet Probabilities

Inside bets offer higher rewards because the probability of winning is significantly lower. A straight-up bet on a single number has a probability of 2.7% in European Roulette. While the payout is 35:1, the mathematical edge remains with the house.

Probability Comparison Chart

• Single Number: 2.7% chance | 35:1 Payout
• Split (2 numbers): 5.4% chance | 17:1 Payout
• Street (3 numbers): 8.1% chance | 11:1 Payout
• Corner (4 numbers): 10.8% chance | 8:1 Payout
• Dozen/Column: 32.4% chance | 2:1 Payout

The Impact of the Zero

The presence of the zero is what ensures the casino always has an advantage. In American Roulette, the addition of the double zero (00) drops the probability of an outside bet from 48.6% to 47.4%. While this seems like a small difference, over hundreds of spins, it significantly increases the house edge and decreases the player's expected return.