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On a European wheel EVERY bet has the same 2.7% house edge (the zero): the bets differ only in volatility, not value. American double-zero wheels double the edge to 5.26%: never the better wheel. No system, progression or pattern changes any of this. If gambling stops being fun, GamStop and GambleAware are free.
What The Roulette Odds Calculator Works Out
- Chance of winning: the pockets your bet covers divided by the 37 on a European wheel. Red covers 18 (48.6%), a dozen 12 (32.4%), a single number 1 (2.7%).
- Average loss per spin: the wheel pays out as if there were 36 pockets but has 37, so every bet surrenders one thirty-seventh of the stake on average: GBP 10 a spin costs 27p in expectation whether spread on red or planted on 17. That is the 2.7% house edge, identical across bets that differ only in how bumpy the ride is.
- Expected cost per hour: loss per spin x spins per hour. A busy online table runs 40 or more spins an hour; a live table nearer 30. This is the price of the entertainment, comparable to any other night out so long as it is priced as spending rather than investing.
- Wheel (advanced): the American double-zero wheel has 38 pockets and the same payouts, doubling the edge to 5.26%, so "which wheel" is the one consequential decision a roulette player gets. La partage, offered on some European tables, returns half the stake on even-money bets when zero lands, halving their edge to 1.35%, the game's one genuine discount.
- Payout if you win (advanced): stake x (36 / pockets covered - 1): 1 to 1 on red, 2 to 1 on a dozen, 35 to 1 on a single number.
- Expected loss this session (advanced): loss per spin x spins per hour x hours played, with the total amount wagered alongside.
- Chance of finishing ahead (advanced): a normal approximation using the bet's variance. Over a short session on red it is a little under 50%; over hundreds of spins it shrinks steadily, because the edge is fixed and the luck averages out. Single numbers give a smaller chance of being ahead but a bigger win when you are.
- Your money lasts on average (advanced): the money taken to the table divided by the average loss per spin. A losing streak empties it far sooner, which is where the Martingale and other progressions meet table limits and finite bankrolls. Systems rearrange variance; the edge collects its thirty-seventh regardless.
- Please gamble responsibly: budgets set before play are the only working system, and GamStop, GambleAware and the operators' deposit limits exist for exactly the moment the entertainment frame slips.
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