What is closing line value?

Closing Line Value measures whether you beat the market: it compares the odds you took against the final odds just before the event started. Bet +150 on a line that closes +120 and you hold about +13.6% CLV. Consistently positive CLV is the strongest known predictor of long-term profit.

How do you calculate CLV?

Convert both prices to decimal and divide: CLV % = (your decimal odds ÷ closing decimal odds − 1) × 100. For a rigorous figure, de-vig the closing price first so the book's margin isn't counted as your edge.

Any consistently positive average is meaningful. A sustained +1% to +3% across hundreds of bets indicates you reliably beat the market. Individual large CLV results mean little — the average over a large sample is the signal, and it stabilizes much faster than win rate does.

Can you have positive CLV and still lose money?

Yes, over any short run — CLV measures the quality of the price you took, not the outcome of the game. It can also happen persistently if you bet markets whose closing lines aren't sharp, or if your staking is too aggressive for your edge to survive the variance.

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Math & measurement

Closing Line Value (CLV)

The difference between the odds you took and the closing odds, expressed as a percentage: bet +150 on a line that closes +120 and you hold about +13.6% CLV. Because the close is the market's sharpest price, consistently positive CLV is the strongest known predictor of long-term winning.

CLV stabilizes much faster than win rate — variance can hide your true skill in wins and losses for hundreds of bets, but whether you systematically beat the closing number shows up quickly and persists.

The formula, worked through

Convert both prices to decimal and divide: CLV % = (your decimal odds ÷ closing decimal odds − 1) × 100. Take +150 on a line that closes +120. In decimal that's 2.50 and 2.20, so 2.50 ÷ 2.20 − 1 = 0.136, or +13.6% CLV.

The sign is what matters, not the size of any single number. A +13.6% result on one bet tells you almost nothing; a positive average across two hundred bets tells you a great deal, because it means you are systematically getting prices the market later disagrees with.

De-vig the close first, or you'll flatter yourself

Comparing against the raw closing price counts the bookmaker's margin as if it were your edge. Suppose you take Team A at +100 and the game closes −110 / −110. Raw CLV looks like 2.00 ÷ 1.909 − 1 = +4.8%, which seems excellent.

But a −110/−110 close de-vigs to 50/50, meaning the fair closing price was +100 — exactly what you got. Your real edge was zero. The entire +4.8% was the vig you happened to be standing on the right side of. Strip the margin from the close before you compare, and the flattering number disappears.

Why it predicts better than your win rate

Win rate is a noisy estimator. At a genuine 54% edge you can run below break-even for a hundred bets without anything being wrong, which makes it nearly useless as short-run feedback. CLV measures the decision rather than the outcome, so it converges far sooner.

That is also the honest limitation: CLV tells you that you beat the market's number, not that you will be paid. Our own research on a 65%-accurate NBA model found it losing money against real closing lines — accuracy and market-beating are different things, and CLV measures the second.

Where it misleads

CLV is only meaningful where the closing line is sharp. In thin markets — obscure props, low-limit futures, small-book-only lines — the close is not a consensus of informed money, so beating it proves little.

It also says nothing about staking. Consistently positive CLV on wildly oversized bets can still bankrupt you before the edge pays out, which is why CLV and bankroll discipline are separate problems.

The common mistake: comparing against the wrong closing price

Your CLV is only valid against the closing price of the same market at the same number. Comparing a −3 spread you took against a −2.5 close is comparing two different bets, and comparing your book's close against a sharper book's close mixes two different markets. Use the same line, the same market, and de-vig it — otherwise you are measuring bookkeeping noise and calling it edge.

Go deeper: CLV calculator →

Common questions

What is closing line value?: Closing Line Value measures whether you beat the market: it compares the odds you took against the final odds just before the event started. Bet +150 on a line that closes +120 and you hold about +13.6% CLV. Consistently positive CLV is the strongest known predictor of long-term profit.
How do you calculate CLV?: Convert both prices to decimal and divide: CLV % = (your decimal odds ÷ closing decimal odds − 1) × 100. For a rigorous figure, de-vig the closing price first so the book's margin isn't counted as your edge.
What is a good CLV?: Any consistently positive average is meaningful. A sustained +1% to +3% across hundreds of bets indicates you reliably beat the market. Individual large CLV results mean little — the average over a large sample is the signal, and it stabilizes much faster than win rate does.
Can you have positive CLV and still lose money?: Yes, over any short run — CLV measures the quality of the price you took, not the outcome of the game. It can also happen persistently if you bet markets whose closing lines aren't sharp, or if your staking is too aggressive for your edge to survive the variance.

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