Arbitrage / Field Bet Calculator
Enter your odds and bet amounts to see if you've locked in a guaranteed profit across all outcomes.
Enter American moneyline odds (e.g. -178, +300, -110)
| Team / Outcome | ML Odds | Dec Odds | Bet ($) | Win Pays | Profit/Loss | If |
|---|
What is Arbitrage Betting?
Arbitrage (often called "arb" or "sure bet") occurs when you can place bets across all possible outcomes of an event at odds where every outcome is profitable. This creates a risk-free situation where you're guaranteed to make money regardless of which outcome occurs.
Arbitrage opportunities typically arise due to differences in odds between sportsbooks, movements in odds over time, or in field bets where the probability implied by all odds doesn't sum to 100%. Sharp bettors and syndicates constantly hunt for arbitrage, which is why opportunities close quickly when detected.
When Does Arbitrage Appear?
Cross-book arbitrage: Book A has Team A at -110 and Book B has Team B at -110 on a two-way market. The implied probabilities from both books don't add to 100%, creating an opportunity.
Field bets: A sportsbook offers "Win the Super Bowl" odds for 8 teams, with the rest lumped into "Field" at certain odds. You can bet each individual team and the field, and if the numbers work, lock in profit.
Futures and live arbitrage: You lock in a futures bet at good odds, then as the market moves, you can bet against yourself at live odds to guarantee profit.
Why Is Arbitrage Temporary?
Sportsbooks employ automated odds-adjustment systems and monitor the market 24/7. The moment an arbitrage is detected — either by sharp traders or by competing books — odds will shift to close the gap. Large or obvious arbitrage opportunities rarely last more than minutes. This is why professionals use specialized software to spot and execute arbs at scale.
Additionally, many modern sportsbooks now limit or restrict winners, meaning sustained arbitrage play can get your account closed or limits reduced.
Arbitrage vs. Parlay Betting
Arbitrage is different from typical parlay or multi-leg betting. In a parlay, you're betting on multiple correlated outcomes and hoping all win — you're taking on risk. In arbitrage, you're betting on mutually exclusive outcomes with odds arranged such that every outcome pays. The math guarantees profit. Arbitrage requires no luck or skill prediction — pure odds mathematics.