| Outcome | Odds | Stake | Return |
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Enter at least two decimal prices to see the split.
Arbitrage calculator
Also called a sure bet or surebet calculator. Enter the best odds for each outcome, add your stake, and see how to split it for the same guaranteed return whichever way the match goes.
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What is arbitrage betting?
Arbitrage betting (sure betting, surebets or arbing) means backing every outcome of a market at different bookmakers so the combined return is locked in before a ball is kicked. It works when the books disagree enough that the best price on each outcome, added up, prices the market below 100%.
Enter decimal odds above. When the inverse odds sum to less than 1, an arbitrage exists and the calculator splits your stake so each outcome pays the same. When they sum to more than 1, the difference is the bookmakers' combined margin. There is no sure bet at those prices.
How the stake split works
Each outcome's stake matches its implied probability, so every result returns the same amount. The guaranteed profit is that equal return minus your total stake. It is the same maths a professional uses. The hard part is finding the prices, live, across dozens of books at once.
Frequently asked questions
What is an arbitrage bet (sure bet)?
An arbitrage bet, also called a sure bet, surebet or arb, is when different bookmakers price the same market so far apart that you can back every outcome and lock in a profit whatever happens. It exists because books disagree on the price.
How do I use this arbitrage calculator?
Enter the best decimal odds you can find for each outcome and your total stake. The calculator shows whether an arbitrage exists, the guaranteed profit, and how much to stake on each outcome so every result pays the same.
Why are sure bets so hard to find alone?
A single bookmaker never prices an arbitrage against itself. You need the best price on each outcome across many books at the same moment, and those windows close fast. That cross-book coverage is what KeenOdds automates.
Do I need American odds?
This tool uses decimal odds. If your book shows American or fractional odds, convert them first with our odds converter, then paste the decimal price here.
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