Roulette Odds: European vs American
Compares single-zero and double-zero wheels, returning win probability, payout and the house edge of 2.70% or 5.26% for red/black, column and straight-up bets.
Análise
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Roulette odds: European vs American
The European wheel has 37 slots (0–36, single zero) and a house edge of 2.70%. The American wheel adds a second zero (00), totaling 38 slots and nearly doubling the edge to 5.26%. Outside bets like red/black, odd/even, or high/low pay 1:1, with a winning probability of 18/37 ≈ 48.65% (European) or 18/38 ≈ 47.37% (American). Inside bets (straight up on a single number) pay 35:1 but only hit 1/37 or 1/38 of the time. In the long run, the expected value is always negative: bet $100 on red in American roulette and you lose $5.26 on average per spin.
Applications and context
Used in land-based casinos worldwide, online gambling platforms, and as a textbook example in probability and statistics courses. The double-zero American variant dominates US casinos; European single-zero is the standard in Europe and most premium tables. A French roulette variant adds the la partage rule, halving the edge on even-money bets to ~1.35%.
FAQ
Can a betting system beat the house edge? No. Martingale, D'Alembert and Fibonacci all fail under finite bankrolls and table limits — the math is unchanged.
Is European roulette really better? Yes — the house edge is roughly half that of the American wheel. Always prefer single-zero when given the choice.
What's the worst bet on the American wheel? The five-number bet (0, 00, 1, 2, 3) has a house edge of 7.89% — clearly the worst on the table.
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The results provided by this tool are for general informational and educational purposes only and do not constitute professional, financial, medical, legal, tax or accounting advice. Always confirm important decisions with a qualified professional and official sources.