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EV Calculator

Expected value (EV) is the single number that separates sharp betting from gambling. A positive-EV bet does not guarantee a win (variance runs the short term, and a real edge is hard to find) but it is the metric sharp bettors optimize for over hundreds of bets.

The formula is straightforward: EV = stake × (decimal odds × true probability − 1). If EV is positive, the offered price exceeds the fair price implied by your probability estimate. BetEdge's edge screen runs this exact formula to score every market it surfaces. Enter your numbers below.

Expected value

+€10.00

ROI

+10.00%

How to use the EV Calculator

  1. 1

    Enter your stake in EUR: the amount you plan to bet.

  2. 2

    Enter the decimal odds from the bookmaker (e.g. 2.0 for an even-money line).

  3. 3

    Enter your true-probability estimate as a percentage (e.g. 55 for 55%). Use Pinnacle's closing line as a reference for the sharpest probability estimate.

Worked examples

Example 1: Positive EV

You back Manchester City to win at decimal odds 2.0 with a €100 stake. After comparing Pinnacle's closing line and accounting for market margin, you estimate their true probability of winning at 55%.

EV = 100 × (2.0 × 0.55 − 1) = 100 × 0.10 = +€10. ROI: +10%. A positive-EV bet. The odds are pricing a lower probability than you estimate.

Example 2: Negative EV (avoid)

A retail book offers Dortmund at decimal odds 1.91 (typical juice on a 50/50 line). You estimate their true win probability at 50%, matching the fair price. Stake: €100.

EV = 100 × (1.91 × 0.50 − 1) = 100 × −0.045 = −€4.50. ROI: −4.5%. The bookmaker margin costs you €4.50 per €100 staked even when your probability estimate is correct. Sharp bettors pass on these lines.

FAQ

EV Calculator FAQ

What is expected value in betting?
Expected value (EV) is the average outcome of a bet if you placed it thousands of times. A positive-EV bet means the offered odds imply a lower probability than the true probability, so the bookmaker is underpricing the outcome. EV = (true probability × decimal odds − 1) × stake. Positive EV does not guarantee a win on any single bet, but compounds positively over a large sample.
How do I find the true probability?
The most reliable method is to use Pinnacle's closing line as a proxy for true probability. Pinnacle operates on ~2% margin and attracts sharp money. Its implied probabilities after de-vigging are the best publicly available estimate of true odds. BetEdge's edge screen uses this exact method to score every market it surfaces.
What is a good EV percentage?
Professional sports-betting services typically work in the 1-5% range. Above 5% usually indicates data-quality issues or a bias artefact (e.g. an over-priced longshot) rather than genuine market inefficiency. A small edge can add up over hundreds of bets, but only if it's real, which is why we measure ourselves on calibration rather than a claimed edge.
Why does a positive-EV bet sometimes lose?
Variance. A 55% true probability means the outcome still goes against you 45% of the time. Short-run results can look like random noise even from a strong positive-EV strategy. This is why sample size and bankroll management matter. The edge only reveals itself over hundreds or thousands of bets.
Can I use this for any sport?
Yes. The EV formula is the same regardless of sport: EV = stake × (decimal odds × true probability − 1). Enter any stake, decimal odds, and true probability estimate. The calculator works equally for football, basketball, tennis, or any market where you have a reliable probability estimate.

BetEdge is an analytics and decision-support tool, not a bookmaker and not a tipster service. We don't accept bets or hold funds. For educational and informational purposes only. 18+.

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