Free tools — no signup, nothing stored
Calculators
Every calculator here runs entirely in your browser. Nothing you type is sent anywhere or saved. They're the same formulas described in the guides, made interactive so you can put your own numbers in.
13 tools
What you'll take away
- Convert between odds formats and read the probability behind a price
- Strip margin out of a book to see what the market really thinks
- Turn expected goals into scorelines, totals and both-teams-to-score
- Size a stake, check an accumulator's real cost, and grade your closing line
Calculators
Odds Converter — Decimal, Fractional, American & Implied ProbabilityConvert betting odds instantly between decimal, fractional, and American formats, and see the implied probability behind any price.Free · runs in your browserFair Odds Calculator — Remove the Bookmaker Margin from Any 1X2 BookEnter the three 1X2 prices and see the bookmaker's margin, the market's true (fair) probabilities via the power method, and the fair odds you'd get in a world without the fee.Free · runs in your browserExpected Value Calculator — Is Your Bet +EV?Free expected value calculator. Enter the odds and your win probability to see if a bet is positive or negative EV, and your expected return per stake.Free · runs in your browserKelly Criterion Calculator — Optimal Bet Size From Your EdgeWork out exactly how much to stake. Enter the decimal odds, your win probability, and bankroll to get the Kelly-optimal stake, plus safer half- and quarter-Kelly amounts.Free · runs in your browserBreak-Even Calculator — The Strike Rate Every Price DemandsAny price sets a bar: the percentage of bets you must win just to stand still. Work out the break-even strike rate for any odds, and what your actual hit rate is worth at them.Free · runs in your browserPoisson Calculator — Scoreline, 1X2, Over/Under & BTTS ProbabilitiesTurn two expected-goals numbers into a full grid of scorelines, then read match result, Over/Under 2.5 and BTTS probabilities straight off it — with the Dixon-Coles low-score correction built in.Free · runs in your browserAccumulator Calculator — Payout and the Margin You Actually PayWork out an accumulator's combined odds and returns, and see the number bookmakers never print: the margin compounds with every leg, so a six-fold quietly costs about a third of your stake.Free · runs in your browserArbitrage Calculator — Stake Split and Guaranteed ReturnSplit a stake across every outcome so the return is identical whichever one lands. Shows the guaranteed profit when the book sums under 100% — and the guaranteed loss when it doesn't.Free · runs in your browserClosing Line Value Calculator — Grade a Bet Without Waiting for the ResultCompare the price you took to the price the market closed at, with the bookmaker margin stripped out. CLV tells you whether a bet was good long before the result does.Free · runs in your browserAsian Handicap Calculator: Settle Any Line, Including Quarter BallsSettle any Asian handicap line against any result. Shows exactly where half-wins and half-losses come from, and what a quarter line commits you to before kick-off rather than after.Free · runs in your browserHedge Calculator: Lock In a Result and Price a Cash-OutWork out the stake on the opposite side that makes the result irrelevant, and price what an open bet is actually worth — the only honest way to judge a bookmaker's cash-out offer.Free · runs in your browserRisk of Ruin Calculator: How Big a Stake Your Bankroll SurvivesSimulate a thousand runs of a percentage-of-bankroll staking plan and see how they ended. Severe drawdowns are routine even with a real edge — stake size decides whether you are still there afterwards.Free · runs in your browserDouble Chance & Draw No Bet Calculator: Derive the Fair PriceDerive fair 1X, 12, X2 and draw-no-bet prices from any 1X2 book. Both markets are arithmetic on the same three probabilities, so a quoted price can be checked rather than trusted.Free · runs in your browser