Betting Calculators
Free tools to help you calculate your edge
Arbitrage Calculator
Find guaranteed profit opportunities across two bookmakers.
ARB FOUND
Back & Lay Calculator
Calculate lay stakes for Betfair exchange hedging. Back at a bookmaker, lay on the exchange.
Bonus Bet Turnover Calculator
Convert bonus/free bets into guaranteed cash. Bonus bet stake is not returned — only profit.
No Vig / Fair Odds Calculator
Remove the bookmaker's margin to find true fair odds and probabilities.
Vig Calculator
See exactly how much the bookmaker is taking from both sides of a two-way market.
Kelly Criterion Calculator
Determine optimal bet sizing based on your edge and bankroll.
+EV BET
Conservative Sizing
Expected Value Calculator
Determine whether a bet has positive expected value (+EV).
+EV BET
Odds Converter
Enter odds in any format — decimal (2.50), fractional (3/2), or American (+150 / -200).
Common Odds Reference
| Decimal | Fractional | American | Implied Prob. |
|---|
| 1.50 | 1/2 | -200 | 66.67% |
| 1.80 | 4/5 | -125 | 55.56% |
| 1.91 | 10/11 | -110 | 52.36% |
| 2.00 | 1/1 | +100 | 50.00% |
| 2.50 | 3/2 | +150 | 40.00% |
| 3.00 | 2/1 | +200 | 33.33% |
| 4.00 | 3/1 | +300 | 25.00% |
| 5.00 | 4/1 | +400 | 20.00% |
| 10.00 | 9/1 | +900 | 10.00% |
| 21.00 | 20/1 | +2000 | 4.76% |
Hedge / Cash Out Calculator
Lock in a guaranteed profit on an existing bet by hedging the opposite outcome.
Profit if Original Wins
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