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Spot an arbitrage bet
in seconds.

Enter the best price for each side from two different books. We show if you can back both sides and win the same either way, and how to split your stake.

ArbitrageFree · No sign-up
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Stake on A
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Stake on B
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Profit
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Return %
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An arb exists when (1 ÷ odds A) + (1 ÷ odds B) is below 1. Books limit or ban people who do this, and arbs close fast.

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Arbs are rare and close within minutes. Our model looks for something else: a price that pays more than it should. The free picks show the price and what $10 returns.

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How to find an arb
in 3 steps

  1. Pick your odds format, then enter the best available price on each side from two different books.
  2. Set your total stake. The calculator splits it so every outcome returns the same amount.
  3. Read the verdict: green means you win the same either way, as long as both bets stand. The stake split shows what to bet on each side.

Worked example

Book 1 prices Outcome A at 2.10; Book 2 prices Outcome B at 2.10. The chances the two prices give add up to 95.2%. That is below 100%, so an arb exists. Staking $100 in proportion returns the same either way for a locked +$5.00 (≈ +5.00%).

Arbitrage:
quick answers

What is an arb?

When prices at different books are long enough to back every side and still make money whichever side wins. It happens when the chances the prices give add up to less than 100%.

How do I split the stake?

Split your stake in line with the chance each price gives, so every result pays back the same total.

Why don't I find arbs very often?

Books price closely and change prices fast, so true arbs are rare and short-lived. Books also limit or close accounts that use them.

Bet Better is not a bookmaker and does not accept wagers. This calculator is an educational tool — odds move and books may restrict accounts. 18+ only. Gamble responsibly; if betting stops being fun, seek support.

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