Expected value calculator
Compare your estimated win probability with the sportsbook price. See expected net value and ROI for a single bet.
Your calculation
A worked example
For a $100 stake at +150 and an estimated 45% win probability: (0.45 × $150) − (0.55 × $100) = +$12.50 expected net value. That is +12.5% expected ROI. An individual bet still wins $150 or loses $100.
The math
EV = probability × profit if win − (1 − probability) × stake. Expected ROI = probability × decimal odds − 1.
For positive American odds, decimal odds = 1 + odds ÷ 100. For negative American odds, decimal odds = 1 + 100 ÷ absolute odds.
Common questions
Does positive EV guarantee profit?
No. Positive EV describes an average under an assumed probability, not the result of one bet. An inaccurate probability estimate can turn an apparently positive bet into a negative one.
Where should the probability come from?
It must be your own justified estimate. This calculator does not predict outcomes. A quoted implied probability or an uncalibrated model output is not proof of the true probability.
What if the market can push?
This version assumes no push. For a push-capable market, a complete EV calculation needs separate win, loss and push probabilities and the applicable refund rules.
Keep exploring
Put the numbers in context.
Read CashCord’s matchup research, then talk through the game with the community.
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