Free betting calculator
Arbitrage Calculator
Enter the American odds for both sides of a market from two sportsbooks and your total stake. You'll see exactly how much to bet on each side to lock in the same return whatever happens.
American odds, e.g. +150 or -110
The other outcome, at a different book
Split across both sides
Profit if every bet is accepted
+$1.74
+1.74% return on $100.00 staked
- Stake on side 1
- $49.63
- Returns $101.74
- Stake on side 2
- $50.37
- Returns $101.74
- Combined implied
- 98.29%
- Below 100% means an arb
How it works
Each price implies a probability. When two books disagree enough that the implied probabilities of both outcomes add up to less than 100%, you can back both sides and profit either way.
The stake is split in proportion to each side's implied probability, so both bets return the same amount. Your profit is that return minus the total stake.
p₁ = 1 / decimal₁ p₂ = 1 / decimal₂
arb exists when p₁ + p₂ < 1
stake₁ = total × p₁ / (p₁ + p₂)
profit = min(stake₁ × decimal₁, stake₂ × decimal₂) − total
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Find arbitrage without the spreadsheet
The Smart Lines scans every major sportsbook and surfaces live arbitrage opportunities, with stakes already split.