Free calculators
Betting Tools & Calculators
Free, instant calculators for odds conversion, parlays, staking and value — the arithmetic done exactly, and every assumption it rests on left in plain sight.
Bonuses & wagering
Convert & combine
Odds Converter
Convert between decimal, fractional and American odds, and read the implied probability each price carries — the bookmaker's margin included.
Open →Parlay Calculator
Multiply several legs into one price, see the return if every one of them lands, and how the bookmaker's margin compounds with each leg you add.
Open →Price and margin
No-Vig / Fair Odds Calculator
Strip the bookmaker's margin out of a two-way or three-way market to see the price without it, and how much of every stake that margin is.
Open →Arbitrage Calculator
Test whether two opposing prices leave a gap at all, size both legs to the same return — and see what a voided leg or a limited account costs you.
Open →Dutching Calculator
Split one stake across several selections so each of them returns the same — and see the whole stake you lose if none of them wins.
Open →Check for an edge
Closing Line Value Calculator
Compare the odds you took with the closing price. Across hundreds of bets it measures your prices rather than your luck; a single result measures nothing.
Open →Expected Value (EV) Calculator
Put your own win probability against the price and see the long-run average it implies — an answer only ever as good as the probability you typed in.
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