Closing Line Value, in plain words
Closing line value, or CLV, is the difference between the price you took and the market's price when betting closed. If you bet a side at -105 and it closes at -120, you got a better price than the market's final, best-informed number. That is positive CLV.
CLV matters because results are noisy and the close is not. A good bet can lose and a bad one can win, so a few hundred results say little. The closing price carries all the information the market had, so beating it again and again is the clearest early sign that your prices are good, long before the wins and losses settle.
Measure it on a fair basis: compare probabilities, not raw prices, and take the margin out of the closing line first. Track it over many bets. A bettor who beats the close on average is getting good numbers; one who loses to it is paying for them, whatever last week's record says.
The idea, drawn
Worked example · illustration
Bet at −105, closed at −120
- Your price
- −105 (51.22%)
- Closing price
- −120 (54.55%)
- Close, fair
- 52.17%
- Edge over the close
- 0.95 pts
- Your −105 implies 51.22%.
- The close was −120 / +100. Taking the margin out leaves 52.17% for your side.
- 52.17% minus 51.22% = 0.95 points of closing line value.
The market's final number said your side was more likely than the price you paid. Do that often and the results follow.