Closing Line Value: The Best Predictor of Long-Term Profit
Win rate is noise. Closing line value is signal. Here's why the line at market close tells you more about your skill than your actual results.
What is closing line value?
Closing line value (CLV) measures whether the odds moved in your favor after you placed your bet. If you bet a line at +150 and it closes at +130, you captured closing line value. You got a better number than the final, most efficient price.
The closing line is the sharpest line. It incorporates all the information the market has absorbed — injury news, weather, sharp money, model updates. It's the closest thing to a "true" probability the market produces.
Why CLV beats win rate
Imagine two bettors over 500 bets:
- Bettor A: 54% win rate, average odds -110. Looks profitable.
- Bettor B: 49% win rate, average odds -105. Looks like a loser.
But Bettor A happened to run hot during a small sample. Bettor B consistently beat the closing line by 3 cents on average.
Over 5,000 bets, Bettor B will almost certainly be profitable. Bettor A might not be.
Win rate is dominated by variance over any reasonable sample size. CLV is a direct measurement of edge. Sportsbooks know this — it's the primary metric they use to identify and limit sharp bettors.
How to calculate it
For each bet you place, record two things:
- Your odds at the time of the bet
- The closing odds just before the event starts
Convert both to implied probability (after removing vig), then:
CLV = Closing Implied Probability - Your Implied Probability
Example: You bet the underdog at +160 (implied 38.5% after de-vig). The line closes at +140 (implied 41.7% after de-vig).
CLV = 41.7% - 38.5% = +3.2%
You captured 3.2 percentage points of closing line value. Over many bets, this translates directly to profit.
What good CLV looks like
Professional bettors typically achieve 2-5% CLV on average. That doesn't sound like much, but it compounds:
- 1% CLV = marginal edge, breakeven after juice in many cases
- 2-3% CLV = solid, sustainable profit
- 5%+ CLV = elite, and you'll likely get limited quickly
If your average CLV is negative, you're consistently getting worse numbers than the closing line. The market is sharper than you are.
How to get CLV
There's no shortcut. You need to be earlier and more accurate than the market:
- Bet early. Lines are softest when they open. The further from close you bet, the more room for the line to move your way.
- Find soft books. Different sportsbooks move at different speeds. Books that are slow to adjust create CLV opportunities.
- Have an edge. Your own model, information advantage, or ability to identify market overreactions.
Track it religiously
Record every bet with opening odds, your odds, and closing odds. After 200+ bets, your average CLV will tell you whether you have a real edge or got lucky.
Use the EV calculator to quantify the expected value at the time of each bet. Use the edge calculator to see whether your overall record reflects skill or variance.
CLV is the scoreboard that actually matters. Everything else is noise.
If you're new to the concept of edge, start with expected value explained — it covers the foundational math behind every profitable bet. And once you know your edge is real, the Kelly Criterion tells you how to size it.