What does an arbitrage calculator do?

An arbitrage calculator works out how to cover both sides of a market when two sportsbooks disagree on price. You enter the odds and the amount you want to bet, and it calculates the matching stake on the other side.

When does an arb exist?

An arb exists when the implied probabilities of the available prices add up to less than 100%. In plain English, the two books have priced the market generously enough that you can cover every outcome and still have money left over.

The important catch

The profit is only locked if both bets are placed at the odds shown. If one sportsbook moves the price before you place the second bet, the arb can shrink or disappear.

Account limiting

Arbitrage can increase the chance of limits because you are repeatedly taking prices that are out of line. Some books limit faster than others, so it is worth spreading activity across books and avoiding obvious max-stake arb-only behaviour.

Related calculators

• Free Bet Calculator: convert sportsbook free bets into locked-in profit
• Dutching Calculator: split stake across more than two outcomes
• Lay Bet Calculator: calculate lay stakes and liability
• Odds Converter: convert American, decimal and implied probability