Roulette Math Visualizer
See exactly how much the house edge costs over time
Comparison
European vs. American Roulette
The only difference is one extra green pocket — but it nearly doubles the house edge.
European
Single zero (37 pockets)
2.70%
House Edge
American
Double zero (38 pockets)
5.26%
House Edge
Calculator
Expected Loss Calculator
See how much you'll lose on average over a session.
Reference
All Roulette Bets & Payouts
| Bet Type | Payout | Probability (EU) | Probability (US) |
|---|---|---|---|
| Straight up (1 number) | 35:1 | 2.70% | 2.63% |
| Split (2 numbers) | 17:1 | 5.41% | 5.26% |
| Street (3 numbers) | 11:1 | 8.11% | 7.89% |
| Corner (4 numbers) | 8:1 | 10.81% | 10.53% |
| Six line (6 numbers) | 5:1 | 16.22% | 15.79% |
| Dozen / Column (12) | 2:1 | 32.43% | 31.58% |
| Red/Black/Odd/Even | 1:1 | 48.65% | 47.37% |
Frequently Asked Questions
What is the house edge in roulette?
European single-zero roulette has a 2.70% house edge; American double-zero roulette has 5.26%. This means for every $100 wagered, the casino keeps $2.70 or $5.26 on average.
Does the bet type matter?
No. On a given wheel, every bet (except the 5-number basket bet on American wheels) has the same house edge. Whether you bet on red, a single number, or a column, the math is the same.
Can a betting system beat roulette?
No. Systems like Martingale change the shape of your results (many small wins, occasional large loss) but cannot change the expected value. Over enough spins, every system converges to the same loss rate dictated by the house edge.
Is there any way to get an edge at roulette?
The only known methods are biased-wheel analysis (finding a physically imperfect wheel) and dealer signature tracking (identifying patterns in the dealer's spin). Both are extremely difficult and rarely practical in modern casinos with well-maintained equipment.
Roulette Math: Odds, House Edge & Expected Losses
This free roulette math tool shows you exactly what the house edge costs over time. Compare European (single-zero) vs. American (double-zero) roulette, calculate your expected session losses, and see the complete payout and probability table for every bet type.
The Cost of That Extra Zero
The difference between one green pocket and two seems trivial, but it nearly doubles the house edge — from 2.70% to 5.26%. Over a 3-hour session at $25/spin, that extra zero costs you roughly $60 more in expected losses.