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Closing Line Value (CLV) Calculator

Compare the price you bet with the closing line. See how many points you beat it by, and, with both sides of the close, your bet's estimated edge.

Check your CLV

The last price on your side before the event started.

Add it to remove the vig from the close and estimate your edge.

What beating the close is worth at −110

If you bet −110, your edge depends on the fair (no-vig) probability of the closing line. At −110 you need the fair close at 52.4% just to break even.

Fair closing probability Fair close Your edge at −110
50% +100 −4.55%
51% −104 −2.64%
52% −108 −0.73%
52.4% (break-even) −110 0.00%
53% −113 +1.18%
54% −117 +3.09%
55% −122 +5.00%
56% −127 +6.91%

Understand closing line value

What CLV measures

Closing line value compares the price you got with the last price before the event started. Bet +110 and see it close −115, and you got a better price than everyone who bet at the close.

"Beat the close by" is the gap in implied probability, in percentage points. It needs only your odds and the close on your side.

Why the closing line is the benchmark

By game time the market has absorbed injury news, weather and the biggest bettors' money, so the closing line is its most informed price. Consistently beating it is the most widely used sign of a real edge.

Results are much noisier. A bettor with a small edge can lose over hundreds of bets, and a bettor with none can win. CLV shows up bet by bet.

From CLV to an estimated edge

The closing price still includes the book's vig. With both sides of the closing market, the calculator removes it (the same math as the no-vig calculator) to get a fair probability, then prices your bet against it: fair probability × your decimal odds − 1.

That estimate assumes the close reflects the true odds. It's an estimate for one bet; averaged over many bets, it's the best available read on your edge. See EV & Kelly for sizing.