Closing Line Value Calculator

How to use it

1. 1 Choose an odds format and enter the odds you bet.
2. 2 Enter the closing odds for the same side of the same market.
3. 3 Optionally enter the closing odds of the other side to remove the vig from the close.
4. 4 Read your CLV percent and whether you beat the closing line.

What closing line value is

The closing line is the last price available before a game starts. It is usually the best-informed price of the week because it reflects the most information and the most money. If you regularly bet at better prices than the close, you are buying odds that the market later agrees were too generous.

Positive CLV does not mean a single bet wins. It is a signal about the quality of your prices, and it needs a decent number of bets before it says much. Treat it as evidence, not proof of long-run profit.

The convention used here

CLV is your decimal odds divided by the closing decimal odds, minus 1. Positive means you got a better price than the close. If you add the closing odds of the other side, the calculator first removes the vig from the closing line using the multiplicative method, and compares your price with that fair closing price.

Without the other side, the raw closing price is used. Because the raw close includes the vig, it makes your CLV look larger than it would against the fair close. The probability change is the closing implied probability minus the implied probability of your price, in percentage points.

Worked example

You bet +150 (decimal 2.50, an implied probability of 40.00%). The line closes at +130 (decimal 2.30, an implied probability of 43.48%).

CLV is 2.50 divided by 2.30, minus 1, which is +8.70%. The implied probability moved +3.48 points toward your side, so you beat the closing line.

The formula

Frequently asked questions