EV Calculator (Expected Value Calculator)
Select Odds Type:
$
%
| Expected Value (%) | |
| Expected Value ($) |
What it does
This EV calculator (expected value calculator) shows what a bet wins or loses on average, per dollar, if you made it many times. When your win chance beats the odds' implied probability, the bet is +EV. Worked example: what +EV betting is and how to find +EV bets.
How to use
Pick the odds type and enter the odds.
Enter your win percentage. No-vig odds from a sharp book are a good source.
Add a wager to see EV in dollars, then click Calculate EV.
Worked example
+150 with a 45% win chance
- Decimal odds
- 2.50
- Profit per $1
- $1.50
- EV
- 0.45 × 1.50 - 0.55 = +0.125
- EV per dollar
- +12.5%
- On a $100 bet
- +$12.50
FAQ
How do I calculate expected value on a bet?
EV = win chance × profit - lose chance × stake. A $100 bet at +150 with a 45% win chance: 0.45 × $150 - 0.55 × $100 = +$12.50. The EV calculator does this for any odds format.
What is expected value in betting?
The average profit or loss per bet if you repeated it many times: win probability times profit, minus loss probability times stake.
Where does my win probability estimate come from?
Your own model, no-vig odds from a sharp book, or closing lines. The EV is only as good as this number.
I bet positive EV but keep losing. Is the math wrong?
Probably not. A 55% bet still loses 45% of the time, so judge EV over hundreds of bets, with closing line value as the early signal.
What is the difference between EV and ROI?
EV is the expected profit before you bet; ROI is the actual return on bets already settled. Over enough bets, ROI moves toward your EV.