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Red or black generator

Spin up to 20 colors at once — on a fair coin, a European wheel or an American wheel with its zeros

Pick a wheel and spin. The fair-coin mode is the 50/50 most people imagine; the EU and US modes keep the green zeros that make real roulette pay less than it looks.

Your spin

Pick a wheel and how many spins. Every submit generates a fresh, independent sequence.

Wheel The zeros are what separate a real wheel from a fair coin.

Spins 1 to 20 spins per submit.

Reset

No JavaScript required. No JavaScript required. Colors are generated server-side with a cryptographic random source.

How the math works

Why red is never a coin flip

On a European wheel 18 of 37 pockets are red — 48.6%, not 50%. The zero belongs to neither color, and that missing 1.4% is precisely the house edge on every even-money bet. The American second zero widens it to 5.26%.

Streaks are just what independent randomness looks like: after five reds, the sixth spin is still 48.6% red. The gambler's fallacy is betting as if the wheel remembers.

# true even-money odds

P(red) = 18 ÷ 37 = 48.6% (EU) · 18 ÷ 38 = 47.4% (US)

P(green) = zeros ÷ pockets · fair coin: P(red) = 50%

Methodology

Each spin draws a pocket via random_int (CSPRNG): 18 red, 18 black and 1 or 2 green on the real layouts. P(red) is 18/37 (48.6%) European, 18/38 (47.4%) American — the shortfall from 50% is precisely the even-money house edge.