Expected Value Calculator
How To Use This Calculator
Calculate your expected profit margin for any bet. Enter the odds and your estimated win probability to see if the bet has positive expected value (+EV).
Input the odds from your sportsbook.
The true probability from a sharp book or model.
Positive EV = profitable bet over time.
What is Expected Value (EV)?
Expected Value (EV) measures the average profit or loss you can expect from a bet over time. It's the most important concept in professional sports betting.
A positive EV (+EV) bet means you have an edge over the sportsbook. While you won't win every bet, consistently placing +EV bets leads to long-term profits because the math is on your side.
EV = (Win Prob × Profit) - (Loss Prob × Stake)Example Calculation
- $100 bet on the Lakers
- Sportsbook odds: +110
- Sharp book shows: -105 both sides
- Fair odds: +100 (50% probability)
Step-by-Step EV Calculation
You find the Lakers at +110 on your sportsbook. Pinnacle has both sides at -105, giving a fair probability of 50%. You want to bet $100.
Common Mistakes to Avoid
Sportsbook odds include the vig, so implied probabilities are inflated. Always use devigged odds from a sharp book to get the true win probability for EV calculations.
EV betting requires a large sample size. Losing streaks are normal — you might lose 10 +EV bets in a row. Quitting too early means you never realize the long-term edge.
Odds change constantly. A +EV bet at the time you calculated it might not be +EV when you actually place it. Always verify odds haven't moved before betting.
Finding a +EV bet doesn't mean you should bet your entire bankroll. Use the Kelly Criterion to size bets appropriately and protect against variance.
Frequently Asked Questions
How do I find the true win probability?
Use our No-Vig Calculator to remove the bookmaker's margin from sharp book odds (like Pinnacle). The resulting "fair" probability is your best estimate of the true win probability.
Can I lose money on +EV bets?
Yes, in the short term. Expected value is about long-term averages. You might lose 10 +EV bets in a row, but over hundreds of bets, you'll profit if your edge calculations are accurate. This is why bankroll management is crucial.
What EV% should I look for?
Any positive EV is technically profitable, but most professional bettors target 2%+ EV to account for estimation errors. Higher EV bets are rarer but more valuable. Our +EV Bet Finder helps you find these opportunities.
Why is EV more important than win rate?
Win rate doesn't account for odds. A 60% win rate on -200 favorites loses money, while a 40% win rate on +300 underdogs is profitable. EV considers both probability and potential payout to give the true picture of profitability.
What is closing line value (CLV)?
Closing line value measures whether the odds you bet at were better than the final odds before an event starts. Consistently beating the closing line is the strongest indicator of long-term profitability — even more reliable than short-term win rate.
How many bets do I need for EV to work?
EV betting requires a large sample size. Most professionals recommend at least 500-1,000 bets before judging results. In the short term, variance can cause significant swings, but over thousands of +EV bets, results converge toward the expected value.
What is the difference between EV betting and value betting?
EV betting and value betting are essentially the same concept. Both involve finding bets where the odds are better than the true probability. "Value betting" emphasizes finding mispriced odds, while "EV betting" focuses on the mathematical expected return. Both strategies lead to long-term profit.
Why +EV Betting Works
Consistently placing +EV bets ensures long-term profitability. Even if you lose individual bets, the math is on your side. Combine this with proper bankroll management using the Kelly Criterion for optimal results.