Player prop calculator: break-even, edge and EV
Enter the Over and Under odds, or just one side, to see the hit rate the price requires. Add your own estimate to calculate edge and expected value. Free, no account.
Enter the prop prices
Enter one side or both.
Enter one side or both.
Your own estimate, from 0 to 100.
Applies to the Over when both prices are entered, otherwise to the side you entered. The other side uses the remaining rate.
- Break-even hit rate (Over)
- 52.38%
- No-vig fair probability (Over)
- 50.00%
- Edge
- Add your hit rate
- EV per $100
- Add your hit rate
Under 52.38%
Under 50.00%
Under Add your hit rate
Under Add your hit rate
Break-even at −110 = 110 ÷ (110 + 100). EV = hit rate × profit − miss rate × stake.
Based on your hit-rate estimate. Assumes the same line on both sides and no pushes.
How to calculate break-even hit rate (worked example)
For negative American odds, divide the absolute odds by the absolute odds plus 100. For positive odds, divide 100 by the odds plus 100. Multiply by 100 for a percentage.
−110: 110 ÷ 210 = 52.38% break-even
Both sides −110: 52.38% ÷ 104.76% = 50.00% fair
Your rate 55%: 55.00 − 52.38 = +2.62 pts edge
EV per $100: 0.55 × $90.91 − 0.45 × $100 = +$5.00
The example rounds for display; the calculator keeps full precision. The no-vig calculation divides each side's implied probability by the sum of both sides. Use the vig calculator to inspect that margin.
What edge and EV mean for a prop
Edge is your estimated hit rate minus the price's break-even rate, in percentage points. EV weights the profit if the bet wins against the stake lost if it misses. At −110, a $100 stake earns $90.91 in profit on a win.
Positive EV means the price works with your estimate. It does not validate the estimate or predict a single result. These formulas assume a win or loss; a whole-number line that can push needs a separate push estimate.
Where your hit rate comes from
Start with his actual games at the same line. Check the sample, minutes and role before using a past rate as your estimate. Check his real hit rate for this prop to see the evidence, then read how to read prop hit rates for what that sample can and can't tell you.
Frequently asked questions
What hit rate do I need to break even at −110?
At −110, the break-even hit rate is 110 ÷ (110 + 100), or 52.38%. Your estimate needs to exceed that rate for positive expected value at that price.
Can I calculate a prop with only one side's odds?
Yes. One price is enough for break-even probability, plus edge and EV if you enter your hit rate. No-vig fair probability needs both the Over and Under prices for the same player, market and line.
Is the no-vig fair probability the player's real chance?
No. It removes the margin proportionally from the two quoted prices. It is a market reference, not a measured hit rate or a prediction of the next game.
Which side does my hit-rate estimate apply to?
When both prices are entered, your estimate applies to the Over and the Under uses 100% minus that estimate. With only one price, it applies to that side. These calculations assume a win or loss, with no pushes.
What does EV per $100 mean?
It is the estimated average net profit or loss per $100 staked if your hit-rate estimate is accurate. At −110 and a 55% hit rate, 0.55 × $90.91 − 0.45 × $100 gives +$5.00. It is not the payout on a single bet.
Can I use a recent hit rate as my estimate?
You can use it as a starting point, but check how many games it covers and whether the same line was used. Minutes, role, injuries and opponents can change. A past hit rate is not the probability of the next result.
Does this work for NFL player props?
Yes. The same American-odds formulas apply to NFL, NBA, MLB and other player props. Use the Over and Under prices for the exact same line. Whole-number lines can push; the displayed EV does not model pushes.