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  1. Home
  2. Gambling Tools

Roulette Odds Calculator

Calculate the probability and expected value for any roulette bet

Formula:Probability = Numbers Covered / Total Pockets

Bet Calculator

Select your wheel type and bet

Inside Bets
Outside Bets
Straight Up
2.70% chance
Covers 1 number
Payout
35:1
Win Amount
$350
EV per Bet
-$0
House Edge
2.7%
Win Probability2.70%
On average, this bet wins about 3 times out of 100 spins

Common Bets

Explore popular roulette bets

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.