Expected value calculator
Put a dollar value on your edge using stake, offered odds, and your fair win probability.
▲$12.50
At +150 with a 45% win chance, $100 makes $12.50 on average.
- Expected ROI
- 12.50%
- Break-even
- 40.0%
- Profit on a win
- $150.00
Your win chance is your own estimate, such as the fair chance from No-vig fair odds.
How to use the expected value calculator
Expected value estimates the average result of repeatedly placing the same bet at the same price. Positive EV means your estimated win rate clears the break-even rate.
- 1Enter the offered odds and your stake.
- 2Add your fair estimate of the outcome's win probability.
- 3Review expected profit and ROI before deciding whether the edge is meaningful.
Formula and assumptions
EV = win probability × profit when winning - loss probability × stake.
The output is only as reliable as your projected probability. It does not account for limits, price movement, or estimation error.
The math in full, with worked examples: What is positive EV betting?
Questions
Answers about this free expected value calculator, sports betting odds, payouts, and the math behind each result.
- It is a wager where your estimated probability produces a positive average return at the price offered.
- No. Expected value describes a long-run average, while any single wager can still win or lose.