Arbitrage Calculator

Enter the two opposing prices and your total stake. We return the arb margin, how much to put on each side, and the profit you lock no matter which way it lands.

The Two Prices

Outcome A Odds (Book 1)

Outcome B Odds (Book 2)

Total Stake to Split ($)

Arb margin—

Stake on A—

Stake on B—

Payout either way—

Guaranteed profit—

Return on stake—

—

What an arbitrage is

An arbitrage, or "arb," exists when two books price opposite sides of the same market so generously that you can back both and profit no matter the result. It happens when the combined implied probability of the two best prices is under 100%. The arb margin is 1 - (1/decimalA + 1/decimalB): positive means risk-free profit, negative means betting both sides just locks in the hold.

How to use it

Enter both prices and the total you want to stake. The calculator splits the stake so the payout is identical either way, and shows the guaranteed profit and return. Arbs move fast and books limit accounts that hammer them, so confirm both prices are still live before placing. To find arbs across every book automatically, use the Hedge Finder arb scan, and learn the mechanics on the Arbitrage Betting explainer.

Keep Going

The Odds Gap holds every book's price, so you do not have to type them in by hand. Skip straight to the live tools:

Line Shop +EV Plays Hedge Finder Arb Scan Top Gaps

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