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Expected Value Calculator
Calculate the EV of any bet. Use your own probability estimate, or compare against a sharp book line to find +EV opportunities automatically.
Your Bet
Decimal: 2.100 · Breakeven: 47.6%
Your honest estimate of how often this bet wins.
Expected Value
Long-term, every $100 you bet on this exact wager makes you $15.50 on average.
What this means
Your estimate of 55.0% beats the breakeven rate of 47.6% by 7.38 points — that's your edge.
Implied Probability Reference
| American | Decimal | Breakeven Win Rate |
|---|---|---|
| -300 | 1.333 | 75.0% |
| -200 | 1.500 | 66.7% |
| -150 | 1.667 | 60.0% |
| -110 | 1.909 | 52.4% |
| +100 | 2.000 | 50.0% |
| +120 | 2.200 | 45.5% |
| +150 | 2.500 | 40.0% |
| +200 | 3.000 | 33.3% |
| +300 | 4.000 | 25.0% |
Find +EV bets automatically
Stop calculating one bet at a time.
This calculator works one bet at a time. TrueLine runs the same de-vigged EV comparison across 10 Canadian sportsbooks against Pinnacle's fair line automatically — re-checking every book on each 30-minute snapshot, so +EV gaps surface without you working a spreadsheet.
How the math works
The expected value formula:
EV = (winProb × profit) - (lossProb × stake)
In By Win Probability mode, you provide your honest estimate of the true win probability. The calculator compares it to the implied probability of the odds you're getting.
In vs. Sharp Book mode, the calculator estimates the true probability by de-vigging the sharp book's two-sided market. This removes the sportsbook's built-in margin to estimate the true fair value:
fair_p = implied_p / (implied_p + opposing_implied_p)
The de-vigged probability assumes both sides of the market share the vig proportionally. It's an approximation, but a useful one — when a sharp book offers different prices than a recreational book, the difference between de-vigged sharp and recreational lines is a reasonable estimate of EV.
All math runs in your browser. We don't log or store your inputs.
Frequently asked questions
What is expected value (EV) in sports betting?
Expected value is the average dollar return per dollar staked if you placed the same bet an infinite number of times. Positive EV means the bet is profitable long-term; negative EV means it's unprofitable. EV is calculated as (win probability × profit) - (loss probability × stake).
How do I calculate EV on a sports bet?
EV % = (winProb × (decimal_odds - 1)) - (1 - winProb). Multiply that by your stake to get the dollar EV. If positive, the bet is profitable long-term; if negative, you'd lose money over volume.
What's the difference between EV and CLV?
EV is forward-looking — it tells you whether a bet should be profitable based on your probability estimate. CLV (closing line value) is backward-looking — it tells you whether the market agreed with you by comparing your odds to the closing line. Both metrics are essential for serious betting analytics.
Is this calculator free?
Yes, completely free. No signup, no rate limit. The math runs entirely in your browser — we don't store any of your inputs.