Arbitrage (Surebet) Calculator

Enter the best odds for each outcome — at different bookmakers — and your total stake. If the implied probabilities sum below 100%, the calculator splits your stake for an equal, guaranteed return.

Arb margin
Stake 1
Stake 2
Guaranteed profit

The maths

Sum the implied probabilities using the best available price for each outcome: Σ = 1/odds₁ + 1/odds₂ (+ 1/odds₃).

Example: 2.10 (book A) and 2.05 (book B). Σ = 0.4762 + 0.4878 = 0.9640 → a 3.73% arb. £100 splits £49.40 / £50.60 and returns £103.73 whichever side wins.

What the arb guides don't tell you

If you do arb, the one thing you can't skip is honest accounting of every leg — including the broken ones. That's exactly what scan-and-track is for: Zort logs both sides at both books and shows your true arb ROI, not the theoretical one.

FAQ

Is arbitrage betting legal?

Yes in the UK and most jurisdictions — it breaks no law. It does breach some bookmakers' terms, which is why accounts get limited or closed.

What's the difference between arbitrage and dutching?

Arbitrage uses different bookmakers' best prices to cover all outcomes at a guaranteed profit. Dutching splits a stake across several selections in the same market (usually one book) for an equal payout — typically without covering every outcome.

Can I arb with a free bet?

Yes — "matched betting" is arbitrage where the bookmaker's promotion supplies the edge. The same stake-splitting maths applies with the free-bet value added to one side.

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