Roulette Odds Calculator
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Quick Answer
Key concepts at a glance
Roulette odds depend on the wheel type and bet. European (single zero): straight bet wins 1 in 37 (2.7%), pays 35:1. American (double zero): straight wins 1 in 38 (2.63%), pays 35:1. Even-money bets (red/black) win 48.6% (European) or 47.4% (American). For a $10 straight bet: expected win = $350, probability = 2.7%, EV = -$0.27 (European).
Key Facts About Roulette Odds
Essential knowledge
- European wheel has 37 pockets (0-36), American has 38 (0, 00, 1-36)
- All bets have the same house edge on a given wheel (except five-number on American)
- European house edge: 2.70%, American: 5.26%
- Straight bet (single number) pays 35:1
- Even-money bets (red/black, odd/even, high/low) pay 1:1
- The five-number bet (American only) has worst odds: 7.89% house edge
- En prison/la partage rules reduce even-money house edge to 1.35%
Frequently Asked Questions
Common questions about roulette odds
What are the odds of hitting a single number?
On European roulette, each number has a 1/37 (2.70%) chance of hitting. On American roulette, it's 1/38 (2.63%). If you bet $10 on a single number and win, you get $350 plus your $10 back. Despite the 35:1 payout, the house edge makes this a negative expectation bet.
Which bets have the best odds?
On European wheels, all bets have the same 2.70% house edge except when en prison/la partage rules apply (reducing it to 1.35% on even-money bets). On American wheels, avoid the five-number bet (0, 00, 1, 2, 3) which has a 7.89% house edge. Otherwise, all American bets have 5.26% edge.
Is European or American roulette better?
European roulette is significantly better with 2.70% house edge vs 5.26% American. Over 1000 bets of $10, you expect to lose $27 on European vs $52.60 on American. Always choose European when available.
Do betting systems work in roulette?
No betting system can overcome the house edge. Martingale, Fibonacci, Labouchere, etc. may show short-term wins but mathematically cannot beat the odds. They often increase variance and risk of large losses. The house edge applies to every bet regardless of previous results.