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    House edge calculator

    See the built-in mathematical advantage on every casino game. Calculate how much the house edge costs you over time.

    House edge by casino game

    GameHouse EdgeRTPNotes
    Blackjack (basic strategy)0.50%99.50%Varies by rules; without strategy ~2%
    Blackjack (average player)2.00%98.00%Most players don't use perfect strategy
    Baccarat (banker bet)1.06%98.94%Best standard baccarat bet
    Baccarat (player bet)1.24%98.76%Slightly worse than banker
    Baccarat (tie bet)14.36%85.64%One of the worst bets in the casino
    European roulette2.70%97.30%Single zero
    American roulette5.26%94.74%Double zero — significantly worse
    French roulette (La Partage)1.35%98.65%Half stake returned on even-money bets when 0 hits
    Craps (pass/don't pass)1.41%98.59%One of the best bets in the casino
    Craps (proposition bets)11–17%83–89%Avoid these entirely
    Online slots (average)3–5%95–97%Varies widely by game
    Online slots (high RTP)1–2%98–99%e.g. Blood Suckers, Mega Joker
    Online slots (low RTP)8–15%85–92%Some branded/jackpot slots
    Video poker (Jacks or Better, optimal)0.46%99.54%With perfect strategy
    Keno25–40%60–75%One of the worst house edges
    Lottery (National Lottery UK)~50%~50%Half of ticket sales go to prizes
    Sports betting (typical)5–10%90–95%Varies by market and bookmaker
    Betting exchange2–5%95–98%Commission-based, usually lower margin

    House edge figures are theoretical and based on optimal play where applicable. Actual results vary. RTP (Return to Player) = 100% minus house edge.

    What the house edge costs you

    Total bets: 60

    Total wagered£600.00
    Expected loss£16.20
    Expected return£583.80
    Cost per hour£8.10

    This is a mathematical average. In any given session, your actual results will vary — you might win more or lose more. But over many sessions, your results will converge toward this expected loss.

    What is the house edge?

    The house edge is the mathematical advantage a casino has on every game. It's expressed as a percentage of your total wager that the casino expects to keep over time.

    A 2.70% house edge (European roulette) means that for every £100 you wager, you can expect to lose £2.70 on average. The casino doesn't win every bet — but over thousands of bets, the maths guarantees they come out ahead.

    What is RTP?

    RTP (Return to Player) is the flip side of the house edge. If the house edge is 2.70%, the RTP is 97.30% — meaning 97.30% of all money wagered is returned to players as winnings over time.

    When you see an online slot advertised as '96% RTP', that means the house edge is 4%. For every £100 wagered across all players, £96 is returned as prizes and £4 is kept by the operator.

    Why the house always wins

    The house edge doesn't mean you can't win — you can, and many people do in any given session. It means that the more you play, the more your results will converge toward the mathematical expectation.

    Short sessions are volatile — you might double your money or lose everything. Long sessions smooth out the variance and the house edge takes over. This is why casinos encourage longer play through loyalty programmes, free drinks, and no clocks on the walls.

    Understanding the house edge

    How to use this calculator

    Select a game or enter a custom house edge, set your average bet and number of bets, and the calculator shows your expected loss. This isn't a prediction of what will happen in any single session — it's the mathematical average over many sessions. Think of it as the cost of playing.

    Which games have the lowest house edge?

    If minimising losses matters to you, blackjack with basic strategy (0.5%), video poker with optimal strategy (0.46%), and baccarat banker bets (1.06%) offer the best odds. European roulette (2.70%) is reasonable. American roulette (5.26%), keno (25%+), and low-RTP slots (8–15%) have some of the worst odds in the casino.

    Does the house edge mean I'll always lose?

    In any single session, no — you can absolutely win. The house edge is a long-term statistical average. In the short term, variance dominates. You might have a great night at the roulette table or a terrible one. But over hundreds or thousands of bets, the mathematics converge. The more you play, the more certain the house edge becomes.

    Frequently asked questions

    The house edge is the percentage of each bet that the casino expects to keep over time. A 5% house edge means the casino keeps £5 out of every £100 wagered, on average. It's the built-in mathematical advantage that ensures casinos are profitable in the long run.