Free betting calculator
Expected value calculator
Estimate the average profit or loss per wager from your win probability, the offered American odds, and your stake.
Enter positive odds with a plus sign or number, and negative odds with a minus sign.
A calculated edge is an estimate, not a guarantee. Your result is only as reliable as the probability input.
What the result means
Use the number as an estimate
Expected value combines every possible outcome by multiplying each result by its probability. A positive result means your assumptions imply a favorable average return over many comparable bets; it does not predict the result of this bet.
At +120, a $100 stake profits $120. If your estimated win probability is 50%, EV is (0.50 × $120) − (0.50 × $100) = +$10.
How to use it
Check the inputs before the output
- 01
Enter the exact American price available to you.
- 02
Enter your own estimated win probability—not the book’s implied probability.
- 03
Review EV in dollars and as a percentage of stake, then test how sensitive it is to your probability input.
Important limits
What the calculator cannot verify
- A weak probability estimate can make positive EV an illusion.
- One result can differ sharply from the long-run average.
- Limits, movement, and settlement rules can change the executable price.
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