Arbitrage Calculator
Enter the odds for each outcome and your total stake. The calculator instantly tells you whether an arbitrage (sure bet) exists, the guaranteed profit %, and exactly how much to stake on each side so your return is the same whoever wins.
How to use it
- Pick 2 outcomes (e.g. tennis) or 3 outcomes (e.g. football 1-X-2).
- Enter the best available decimal odds for each outcome, ideally from different bookmakers or a betting exchange.
- If a leg is on an exchange, enter its commission % (otherwise leave it at 0).
- Set your total stake. The calculator shows the stake per outcome and whether it's a sure bet.
How the maths works
An arbitrage exists when the sum of 1 / odds across all outcomes is less than 1. The guaranteed profit percentage is (1 / sum) − 1, and each stake is (1/odds) / sum × total so the return is identical whichever outcome wins. For the full breakdown with a worked example, see how to calculate a sure bet.
What the commission field does
Betting exchanges charge a commission on net winnings, which lowers a leg's effective odds. Enter that percentage and the calculator adjusts automatically — an arbitrage that looks positive before commission can turn marginal after. See how betting exchanges work.
Note
Stakes are rounded to two decimals, so real returns can differ by a cent or two. Odds also move within seconds — by the time you place both legs by hand, the margin may be gone. That's the problem ArbPlay solves automatically.
Related: What is arbitrage betting · How to calculate a sure bet · all guides.