Closing line value, explained
The closing line is the last price before a game starts. By then the market has absorbed the injury reports, the lineup news and the money from people who bet for a living. Closing line value, or CLV, measures whether the price you took was better or worse than that final price.
How to measure it
Say you take a player's Under 24.5 points at -110. The no-vig probability of the under at that moment is 50.0% (using a -110 / -110 market). At tip-off the same line is Over +105 / Under -125. Remove the vig (how): the under is now about 53.2%. The market moved toward your side by about 3.2 points of probability. That is positive CLV.
If instead the closing price had been Over -125 / Under +105, the under would close near 46.8%, and you'd have about 3.2 points of negative CLV: you took a worse price than the market settled on.
Two practical notes. Measure against the same line; if the line moved from 24.5 to 23.5, the comparison needs a conversion and gets noisy. And measure against a sharp closing price where you can, because a recreational book's close can still carry its own shading (why Pinnacle).
Why bettors care
Results are slow. At typical prop prices, the luck in a few hundred bets can easily swamp a real edge of a few percent, in either direction. Closing line value accumulates faster, because each bet gets its own measurement whether it wins or loses. A bettor who consistently gets better prices than the close is, on average, betting into prices that the market later agreed were wrong.
What CLV doesn't prove
- It isn't profit. Positive CLV that's smaller than the margin you pay still loses money over time.
- Closing prices are estimates. Thin prop markets close less efficiently than game lines, so a single close is a noisy benchmark.
- Selection can fool you. If you only bet lines that later move your way for reasons you couldn't have known, the average looks good without any skill behind it.
- Small samples still lie. CLV needs fewer bets than results do, not none.
How the board relates to this
The board's states describe the same idea in real time. A pick is LIVE while the price that qualified it is still available. MOVED means DraftKings has moved toward Pinnacle and the gap is gone at today's price; see why lines move. OpenSlate publishes prices and states, not a results ledger; whether to act on any of it is yours to decide.
A simple way to track it yourself
Keep a log with four columns: the line, the price you took, the closing price on the same line at a sharp book, and the time you placed it. Convert both prices to no-vig probabilities and subtract. Averaged over a few hundred bets, the number tells you more about your process than the win-loss column will for a long time. If the average is negative, the market is consistently disagreeing with the prices you take, and no streak of wins changes that.
More: Removing the vig: how to turn two prices into a fair probability · Why Pinnacle is the reference price · Why parlays cost more than the same bets straight · Why player prop lines move · Is DraftKings or Pinnacle sharper on NBA player props? · How do I calculate a no-vig price? · What is a +EV player prop? · Why do DraftKings and Pinnacle prop lines differ? · What is a Trap Over? · Are NBA rebound unders profitable? · How do I compare sportsbook prop odds for free? · What does closing line value tell me? · How often do prop lines move before tip-off? · What is the vig on DraftKings player props? · How do injury reports move NBA prop lines? · What is a market-maker sportsbook? · Is it better to bet the over or the under on player props? · Can you make money betting player props? · Can you bet at Pinnacle from the US? · What free tools help with player prop betting? · Does betting DraftKings when it disagrees with Pinnacle work? · What does over/under mean on a player prop? · How do sportsbooks set player prop lines? · What is a sharp bettor? · How do I convert American odds to implied probability? · What is a steam move in sports betting? · What are alternate lines on player props?
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