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    Free tool

    Kelly criterion calculator

    How much of your bank a bet with an edge deserves.

    Your bet

    The price you can get, and how likely you think it is to win.

    Your estimate
    0
    0
    %
    $
    1000
    Kelly fraction

    Recommended stake

    Bigger edge, bigger bet. No edge, no bet.

    Fill in the numbers to see the result.

    How it works

    • Kelly fraction = (odds × chance − 1) ÷ (odds − 1).
    • Full Kelly swings hard; most bettors stake a half or a quarter of it.
    • No edge means no bet.

    Betting involves risk. Bookmakers can restrict or close accounts and void bets, automation can fail, prices move, and a positive expected value (+EV) bet can still lose. Promotions carry each bookmaker's own terms. There is no guarantee of profit. See responsible gambling for limits and support.

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    By the B337 team. Last updated 8 October 2026.

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    B337 is software, not a bookmaker or wagering service provider. Bets are placed in accounts you hold with Australian bookmakers. Bookmaker names are trade marks of their owners; B337 is not affiliated with or endorsed by them. Bookmaker terms may restrict automated betting.

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