The math the casino would rather you skip.
House edge, roulette, blackjack, slots, betting systems — the numbers behind every casino game. Free, no sign-up, no tips. The math is the same wherever you play.
House edge
What roulette and blackjack hand the casino on an average session, in money.
OpenHouse edge comparison
Every casino game ranked by edge — the gap between best and worst is a hundredfold.
OpenRoulette odds
Probability, payout and house edge of every roulette bet, across all three wheels.
OpenBlackjack basic strategy
The full chart: the mathematically correct play for every hand.
OpenSlot RTP
What a 96% return to player really costs you, spin after spin.
OpenCraps odds
The only zero-edge bet in the casino, next to the worst ones.
OpenThe gambler's fallacy
After a streak, does the next result change? The two numbers that settle it.
OpenBankroll duration
How many rounds and hours your money lasts at the table.
OpenMartingale debunked
2,000 simulated sessions of the doubling system, and how they end.
OpenBetting systems debunked
D'Alembert, Fibonacci, Labouchere, Paroli — tested over 2,000 sessions.
OpenCasino bonus
What the wagering requirement really costs, and whether the bonus is bait.
OpenLottery
The real value of a ticket and the average wait for a jackpot.
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