Expected Value (EV) Calculator

Expected Value (EV) is the most important concept in profitable sports betting. It represents the average amount you can expect to win or lose per bet over time. Professional bettors focus exclusively on finding +EV (positive expected value) bets.

The EV Formula

EV = (Win Probability × Profit) - (Lose Probability × Stake)

Example: You bet $100 at -110 odds (1.91 decimal) and believe you have a 55% chance of winning:

• Profit if win: $90.91
• EV = (0.55 × $90.91) - (0.45 × $100) = $50 - $45 = +$5.00

This bet has positive expected value. Over many similar bets, you'd expect to profit $5 per $100 wagered.

Finding Your Edge

Your edge is the difference between your estimated probability and the implied probability from the odds. To have +EV, your probability must exceed the break-even probability.

At -110 odds, the implied probability is 52.4%. You need to win more than 52.4% of the time to be profitable. If you estimate 55% win rate, your edge is +2.6%.

Why EV Matters

• Long-term profitability: +EV bets compound over time
• Variance management: Even +EV bets lose sometimes
• Bet selection: Focus on bets where you have an edge
• Bankroll growth: Consistent +EV betting grows your bankroll

Common Mistakes

• Overestimating your probability (be honest about your edge)
• Ignoring the vig (juice reduces your EV)
• Chasing -EV bets for excitement
• Not tracking results to validate your estimates