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CLV & EV: How to Measure Your Edge
August 21, 2026
Two questions came up in our Discord:
“Does this bet actually have an edge? “
“How do we know a strategy is working beyond just wins and losses? “
Both share the same answer: evaluate CLV and EV, not your win rate.
Why Win Rate Doesn’t Prove Anything?
A winning bet tells you almost nothing on its own:
- You can win a badly priced bet through luck.
- You can lose a genuinely great, high-value price due to normal variance.
Judging a betting strategy purely by short-term wins and losses is like judging a stock purchase solely on whether it went up the next day. To measure performance accurately you need two metrics:
- Closing Line Value (CLV): Measures the price you secured against the final market consensus.
- Expected Value (EV): Measures whether a specific bet is mathematically profitable before placing it.
Closing Line Value (CLV): Did You Beat the Market?
The closing line is the final price available right before an event starts. Because it accounts fo all available market information, it represents the most accurate benchmark of true probability.
Comparing your entry price to the closing line proves whether you secured a real edge:
- Positive CLV: You bet Germany at 1.40, and the market closes at 1.35 (you beat the market).
- Zero CLV: You bet Germany at 1.40, and it closes at 1.40 (you got market average).
- Negative CLV: You bet Germany at 1.40, but it drifts to 1.55 by kickoff (the market disagreed with you).
Calculating CLV
CLV is expressed as a percentage to compare value across different odds ranges:
Worked Examples:
- Shortening Line (+CLV): You bet odds of 1.40, and the line closes at 1.35.
- Drifting Line (-CLV): You bet odds of 1.40, but the line drifts to 1.55.
Expected Value (EV): Is This Specific Bet Worth It?
While CLV measures historical execution quality, Expected Value (EV) evaluates a single opportunity before you place it.
EV compares the true probability of an outcome (de-vigged odds from a sharp bookmaker) against the decimal odds offered by a soft bookmaker.
Worked Example:
- De-vigging a sharp market yields a true probability of 60% (0.60) for Team A. Fair decimal odds would be 1÷0.60≈1.67.
- A soft bookmaker offers Team A at 1.85 (implying only a 54.1% probability).
- Calculate EV:
On a €100 stake, an 11% EV yields an expected long-run average profit of €11 per bet:
Why Sample Size Changes Everything?
EV and CLV represent mathematical averages that require specific sample size to smooth out noise.
| Sample Size | Impact of Outliers | Reliability of Metrics |
| 5 Bets | High (a single red card or injury distorts the average) | Low (unreliable) |
| 500 Bets | Low (random variance cancels out) | High (reflects true edge) |
When EV and CLV Disagree
Across a large sample, EV and CLV should align. Mismatches reveal different issues in your process:
- High EV, Negative CLV: Your odds estimate is probably off somewhere. The market keeps disagreeing with the “true” price you’re using.
- High CLV, Low EV: You’re good at getting in early before the price moves. But you’re not checking if the bet is worth it before you place it.
How They Work Together?
- EV determines whether to place a bet.
- CLV confirms post-match whether your entry process maintains a real edge.
Where to Go From Here?
You don’t need to run these formulas manually. BetUnfair’s Bet Tracker automatically logs closing odds against your entry price and calculates CLV for every settled bet. The EV Tool handles pre-bet comparisons across soft and sharp bookmakers.
Start your free 5-day trial at betunfair.io to begin tracking your CLV automatically.
FAQ
What is CLV in betting?
Closing Line Value is the percentage difference between the price you bet and the final closing price right before the event starts.
What is EV in betting?
Expected Value is the mathematical expectation of profit or loss per bet based on fair (de-vigged) odds vs. offered odds.
Can I have positive EV and still lose the bet?
Yes. EV represents long-run profitability across many instances, not a guaranteed outcome for an individual wager.
Is a winning month proof that my strategy works?
No. Short-term profit can stem from positive variance on bad bets. CLV and EV are the true measures of long-term sustainability.
How do I calculate CLV?
CLV=(Your Odds÷Closing Odds−1)×100.
How do I calculate EV?
EV=(True Probability×Decimal Odds−1)×100.
Do I need a large sample size to trust these numbers?
Yes. A small sample is heavily skewed by single events. Hundreds of bets are needed to filter out noise.
What does it mean if my EV looks good but my CLV doesn’t?
It usually indicates that your input model or sharp reference source is inaccurate compared to where the market ultimately clears.
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