Measure your edge / Free calculator
Expected Value Calculator
Expected value combines what you could win, what you could lose, and your estimate of each outcome’s likelihood. Calculate expected profit per bet and expected return on stake.
Your inputs
Instant calculationChanging formats resets odds to even money.
Your results
Based on your inputs. Before fees, rounding, and venue-specific settlement rules.
How to use the expected value calculator
Enter the offered odds, your stake, and an independently estimated win probability. The calculator weights winning profit by that probability and subtracts the weighted loss of the stake.
EV = p × stake × (decimal odds − 1) − (1 − p) × stakeA worked example
At +100, a $100 stake wins $100 profit or loses $100. With an estimated 55% chance of winning, EV is 0.55 × $100 − 0.45 × $100 = +$10, or a 10% expected return on stake.
What the numbers can tell you
The result is only as reliable as your probability estimate. Positive EV is a long-run model average, not the outcome of a single bet. Fees, taxes, slippage, and model error are excluded.
Frequently asked questions
Where should the win probability come from?
Use an independently evaluated model or research estimate. Entering a bookmaker’s raw implied probability simply reproduces that price and does not establish an edge.
Can positive EV bets lose?
Yes. A single positive EV bet can lose its entire stake. Outcomes can vary substantially from the expected average, even across many bets.