Betting calculators

Free calculators for the arithmetic that comes up in betting. Each one runs in your browser, with the formula and a worked example under it, and sends nothing anywhere.

Every calculator

• Arbitrage calculatorType a price for every outcome of a market and one total stake, and the calculator returns the stake on each leg that makes every result pay back about the same.
• Back lay calculator for matched bettingType the back stake, both prices and your own commission rate, and the calculator answers with the lay stake that leaves close to the same amount whichever way the selection goes.
• Bet calculatorType a stake and a decimal price and the calculator shows the outlay, the return and the profit: an illustrative $25 at $4.20 returns $105.00 for an $80.00 profit.
• Bookmaker margin calculatorA bookmaker margin calculator adds 1 / odds across every selection in one market: the total is the market percentage, and everything above 100% is the margin.
• Scratching deductions calculatorThe calculator works out what a winning fixed-odds bet returns once a late scratching's deduction comes off it, from the stake, the price you took and the cents in the dollar.
• Dutching calculatorA dutching calculator works out how much to put on each of several selections in one market so the same amount comes back whichever of them wins.
• Each way calculatorThe calculator shows what an each way bet returns if the runner wins, only places or runs unplaced, counting both halves, so $10 each way is a $20 outlay.
• Expected value calculatorThis expected value calculator works out what one bet is worth on average, in dollars and per $1 staked, from the stake, the price on offer and your own estimate of the chance.
• Fair odds calculatorThis fair odds calculator takes the bookmaker margin out of a market and shows what each selection's price would be without it.
• Flexi calculator for racing exoticsPick the bet type, say how your runners are spread over the placings and type an outlay, and the calculator returns the combinations covered, the flexi percentage and what a dividend pays on that share.
• Hedge bet calculator for an open bet or multiThe hedge calculator sizes a second bet against one you already hold, a lay of your selection or a back bet on the other result, and shows what the pair leaves whichever way it goes.
• Kelly criterion calculatorThe calculator turns a bankroll, a decimal price and your own estimate of the chance into a stake, using the Kelly share edge / (odds - 1).
• Lay bet calculatorThe calculator turns a lay price and your stake into the liability: what you pay if the selection wins, which is the lay stake multiplied by the lay odds minus 1.
• Multi bet calculatorA multi bet calculator multiplies every leg's decimal odds together, then multiplies your stake by that combined price to get the return.
• Odds converterType a price in decimal, fractional or American form, or as a percentage, and the other three formats update as you type.
• Quaddie calculator for doubles, quaddies and the Big 6Pick the pool, type how many runners you are taking in each leg, and the calculator multiplies them: that product is the number of combinations your bet covers.
• Bonus bet converterThe lay stake, liability and cash you keep when a stake-not-returned bonus bet is hedged at an exchange.

The Terminal's own calculators, for hedging a bet at the exchange, valuing a racing promotion, splitting a stake across two bookmakers and dutching a field, sit together on the odds comparison page.