What Is Arbitrage Betting?
Arbitrage betting (also called an "arb") refers to a price gap between bookmakers: the best available odds for every outcome of an event, taken from different bookmakers, imply a total probability under 100%.
An arbitrage exists when the sum of the implied probabilities of all outcomes across the best available odds is below 100%. The size of that gap is the arbitrage margin. For a two-outcome market, an arb exists when 1/oddsA + 1/oddsB < 1.
Arbitrage opportunities are small and short-lived because bookmakers adjust prices quickly, so finding them at scale requires real-time odds from many bookmakers at once. That is why arbitrage tools are built on odds APIs.
Frequently Asked Questions
How do you find arbitrage bets?
You compare the best odds for each outcome across many bookmakers in real time and check whether the combined implied probability is below 100%. Doing this at scale requires an odds API that aggregates many bookmakers with low latency.
Is arbitrage betting legal?
Arbitrage betting itself is generally legal, but individual bookmakers may restrict or limit accounts they identify as arbitrage bettors. Rules vary by jurisdiction and operator.
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