Roulette maths
Roulette odds begin with counting the zeros
Best casinos available in AustraliaUpdated 29 October 2026
WinCrown · Welcome bonus200 free spins on selected slots
Reviews (9,827)
4.9Rating
18+ · Offer terms
18+. Offer wording, rating and review count are reported by the partner and shown as received. Availability and terms depend on where you are. Gambling carries financial risk.
18+ · Offer terms
18+. Offer wording, rating and review count are reported by the partner and shown as received. Availability and terms depend on where you are. Gambling carries financial risk.
European roulette has one zero; American roulette usually has zero and double zero. Extra zero pockets increase the house edge while standard payouts remain the same.
Guide updated 24 September 2026
Roulette maths: the practical details
Red/black is not a true 50–50 wager because zero is neither. Previous spins do not change the probability of an independent next spin.
Key distinctions
- A single-zero wheel has 37 pockets.
- A double-zero wheel has 38 pockets.
- Outside bets still lose when zero appears unless a special rule applies.
Put the information to use
- Count wheel pockets.
- Read zero rules.
- Ignore spin histories.
- Avoid progression systems.
See what SafeCasino has for you today
Open the current lobby to browse games, view the offer shown for your visit and choose the option that fits how you want to play.
View SafeCasino offerPopular question
Is red more likely after five black spins?
No. On a fair wheel each spin is independent; the zeros keep red below a 50% chance.
Keep exploring
More answers on this topic
Volatility tells you how rough the ride can be
Compare low, medium and high volatility games and see how the same RTP can produce sharply different sessions.
Explore this topic →An RNG can be tested; the operator still needs checking
Learn how RNG games select outcomes, what independent testing can establish and why certification is not a legality check.
Explore this topic →Demo play tests controls, not your chance of winning later
Compare configuration, emotion, bet speed, account terms and data collection between free play and real-money modes.
Explore this topic →