Odds Roleta Europeia vs Americana

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.