Expected value calculator
Enter a price, what you think the real chance is, and your stake. Expected value is what a bet returns on average if you could make it many times — positive when your probability is higher than the price implies, and that gap is the only reason to take a bet.
Expected value
+12.50
12.50% of stake · positive expected value at this price
- Break-even probability
- 40.0%
- Your edge
- +5.0%
- Profit if it wins
- 150.00
- Decimal price
- 2.500
Common questions
- How do you calculate expected value in betting?
- Expected value is the chance of winning multiplied by the profit if it wins, minus the chance of losing multiplied by the stake. At decimal odds of 2.50 a stake of 100 wins 150, so a 45% chance gives 0.45 × 150 − 0.55 × 100 = +12.50.
- What counts as a good EV percentage?
- Anything positive beats the price, but the number has to survive the fact that your probability is an estimate rather than a measurement. A small edge disappears if the estimate is slightly wrong, which is why a threshold well above zero is normal.
- What is break-even probability?
- The chance the price itself implies — one divided by the decimal odds. Below it a bet loses money on average however convincing the reasoning behind it is.