Free tools
Betting calculators
Free calculators for the math that matters: strip the vig, price a fair line, size a Kelly stake, and check the value of any bet.
Odds Converter (Decimal, American, Fractional & More)
Convert between decimal, American, fractional, probability and prediction-market cents.
Open calculatorNo-Vig / Fair Odds Calculator
Strip the bookmaker margin from a market and see the fair odds and true probabilities.
Open calculatorClosing Line Value (CLV) Calculator
Compare the odds you took against the closing line to see if you beat the market.
Open calculatorKelly Criterion Stake Calculator
Turn your bankroll, odds and edge into an optimal stake with the Kelly criterion.
Open calculatorExpected Value (+EV) Calculator
Enter the odds and the true chance to see whether a bet is +EV and by how much.
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