Arbitrage Calculator
Enter decimal odds for each outcome from different bookmakers. The calculator tells you whether an arb exists and exactly how much to stake on each outcome to guarantee a profit.
What Is Arbitrage Betting?
Arbitrage (or "arbing") means placing bets on every possible outcome of an event across different bookmakers at odds that guarantee a profit regardless of the result. It works because bookmakers price markets independently and occasionally offer odds that, combined, produce an implied probability below 100%.
For a two-outcome market, an arb exists when: (1 / Odds A) + (1 / Odds B) < 1. The smaller the sum, the larger the profit margin.
How the Stake Calculation Works
For each outcome, your stake is: Total Stake × (1 / Outcome Odds) / Sum of (1 / All Odds). This distributes money so that every outcome returns the same amount, locking in the profit.
Where to Find Arbs
Arbs appear most often during line movements, when one bookmaker is slow to update odds after news. Head-to-head markets in AFL, NRL, and tennis are the most common hunting grounds. Odds comparison sites make it easier to spot pricing gaps across Australian bookmakers.
Frequently Asked Questions
Will bookmakers ban me for arbing?
Licensed Australian bookmakers can restrict accounts at their discretion. Consistent arbing on the same markets at the same bookmaker increases the risk of account limits. Spreading activity across multiple bookmakers and mixing arbs with recreational bets can reduce but not eliminate that risk.
How big are typical arbitrage margins?
Most arbs produce margins between 0.5% and 3%. A 1% margin on a $1,000 total stake locks in $10 guaranteed profit. Margins above 5% are rare and often signal a data error or odds movement that has already closed. Always verify odds directly with the bookmaker before placing.
What is the difference between arbitrage and dutching?
Dutching distributes a total stake across multiple selections at the same bookmaker so they all return the same amount. It does not guarantee a profit because the implied probability sum is above 100%. Arbitrage uses different bookmakers and only works when the combined implied probability falls below 100%.
Can I use this calculator for three-way markets?
Yes. Select "3 Outcomes" to add a third odds field, which covers markets like soccer 1X2 (home win / draw / away win). The same formula applies: sum the implied probabilities and check whether the total is below 1.00. Three-way arbs are harder to find because you need competitive odds from three different bookmakers simultaneously.
This calculator is for informational purposes only. Odds change quickly - always verify with your bookmaker before placing. Gamble responsibly. For free support call 1800 858 858.