Roulette Odds Calculator
Compare roulette bets, payouts, probabilities and house edge for European, American and French roulette. See your expected loss per spin and per session.
Interactive Roulette Odds Calculator
French rules only affect even‑money bets (Red/Black, Odd/Even, High/Low).
Bet statistics
- Numbers covered
- 1
- Payout (including stake)
- 35 : 1
- Win probability
- 2.70%
- Lose probability
- 97.30%
- House edge
- 2.70%
Expected results
- Expected value per spin
- −$0.27
- Expected loss over session
- −$13.50
- Total amount wagered
- $500.00
- Expected return rate
- 97.30%
This tool is for education and entertainment only. It does not encourage or facilitate real‑money gambling.
Roulette odds & house edge by bet type
Quickly compare the main roulette bets. Values assume standard rules with no special side bets.
| Bet | Numbers | Payout | Win % (EU) | Win % (US) | House edge (EU) | House edge (US) |
|---|---|---|---|---|---|---|
| Straight Up | 1 | 35 : 1 | 2.70% | 2.63% | 2.70% | 5.26% |
| Split | 2 | 17 : 1 | 5.41% | 5.26% | 2.70% | 5.26% |
| Street | 3 | 11 : 1 | 8.11% | 7.89% | 2.70% | 5.26% |
| Corner | 4 | 8 : 1 | 10.81% | 10.53% | 2.70% | 5.26% |
| Six Line | 6 | 5 : 1 | 16.22% | 15.79% | 2.70% | 5.26% |
| Dozen / Column | 12 | 2 : 1 | 32.43% | 31.58% | 2.70% | 5.26% |
| Even‑Money (Red/Black, etc.) | 18 | 1 : 1 | 48.65% | 47.37% | 2.70% (1.35% French) | 5.26% |
How roulette odds are calculated
Roulette is a simple probability game: the ball can land in any pocket with (approximately) equal chance. The odds of a bet are determined by how many pockets you cover and how much the casino pays when you win.
Basic probability formula
Win probability for a bet that covers k numbers on a wheel with N pockets:
P(win) = k / N
Lose probability:
P(lose) = 1 − P(win)
For example, a Straight Up bet on European roulette covers 1 number out of 37:
P(win) = 1 / 37 ≈ 2.70%P(lose) = 36 / 37 ≈ 97.30%
Expected value and house edge
The expected value (EV) of a bet is the long‑term average result per unit wagered. For a simple win/lose bet with payout b to 1:
EV per unit = P(win) × b − P(lose) × 1
House edge is the negative of EV, expressed as a percentage:
House edge = −EV × 100%
On European roulette, all standard bets (except special French rules) have the same house edge of about 2.70%. On American roulette, the extra 00 pocket increases this to about 5.26%.
European vs American vs French roulette
- European roulette: 37 pockets (0–36), house edge ≈ 2.70% on all standard bets.
- American roulette: 38 pockets (0, 00, 1–36), house edge ≈ 5.26% on most bets.
- French roulette: single‑zero wheel plus La Partage or En Prison on even‑money bets. When zero hits, you lose only half your stake or it is held for the next spin. This cuts the house edge on even‑money bets to ≈ 1.35%.
Practical tips for using roulette odds
- Prefer single‑zero wheels (European or French) over double‑zero American wheels whenever possible.
- Even‑money bets in French roulette are mathematically the best standard bets in the game because of the reduced house edge.
- Higher payouts do not mean better odds – Straight Up bets feel exciting but have the same (or worse) house edge as safer bets.
- Session length matters: the more spins you play, the closer your results tend to the negative expected value.
Frequently asked questions about roulette odds
Do betting systems like Martingale change the odds?
No. Systems that increase or decrease your stake after wins or losses do not change the underlying probabilities or the house edge. They only change the variance of your results and the risk of going broke or hitting table limits.
Why does the casino always have an edge?
If roulette paid at true odds (for example, 36:1 on a single number in European roulette), the expected value would be zero. Instead, payouts are slightly lower than true odds (35:1), which builds in a small but persistent advantage for the house on every spin.
What is the safest bet in roulette?
“Safest” can mean different things:
- Lowest volatility: even‑money bets (Red/Black, Odd/Even, High/Low) win almost half the time but still have a negative expected value.
- Lowest house edge: even‑money bets on a French roulette table with La Partage or En Prison (≈ 1.35% house edge).
Can I ever get a positive expected value in roulette?
Under standard casino rules with a fair wheel, no. All standard bets have a negative expected value. The only way to gain an edge would be through non‑standard conditions (e.g., biased wheels, dealer signature, or promotions) which are rare and often not sustainable.