Gambling terms, explained straight

Sports Betting

Closing line value (CLV)

Closing line value (CLV) is the difference between the odds a bettor took and the final odds available just before the event starts, used to measure whether the bettor beat the market.

Applies to
Fixed-odds markets, point spreads, moneylines, and totals where opening and closing lines can be compared 43
Positive CLV
When the bettor's odds are better than the closing odds, indicating they beat the market 14
Negative CLV
When the bettor's odds are worse than the closing odds, indicating they lost to the market 14

Key points

  • CLV compares the price a bettor secured with the market's final price just before an event starts, not with the opening line. 14
  • A positive CLV suggests the bettor identified value before the market adjusted, often used by sharp bettors as a performance metric. 1
  • CLV is distinct from betting edge (any advantage over the bookmaker) and from vigorish (the bookmaker's commission). 25

Where this term is used

Not the same as

  • Vig meaning — the bookmaker's commission or margin, not a measure of line comparison
  • Moneyline — a type of bet on which team will win, not a metric for comparing odds
Sports betting Parlay A single bet that links two or more selections, all of which must win to pay out. Sports betting Moneyline A bet on which side will win outright, expressed in odds. Sports betting Spread betting Betting on the margin of victory, with a handicap applied to the favourite. Sports betting Moneyline betting Another term for betting on the outright winner of a game. Sports betting Point spread A handicap given to the underdog to level the betting field. Sports betting Vig meaning The commission or fee the bookmaker charges on each bet.

Sources

  1. A Systematic Review of Machine Learning in Sports Betting arxiv.org Defines CLV as the difference between taken odds and closing odds, and explains how it measures market-beating.
  2. [PDF] Converting College Football Point Spread Differentials to Probability arxiv.org Distinguishes betting edge from CLV and notes no standard CLV formula is given.
  3. Wages of wins:⋆could an amateur⋆⋆make money arxiv.org Confirms CLV applies to fixed-odds markets and line-based bets.
  4. Fixed-odds betting - Wikipedia en.wikipedia.org Provides the fixed-odds betting context and explains how lines move with information.
  5. Vigorish - Wikipedia en.wikipedia.org Clarifies that vigorish is the bookmaker's margin, not a line-comparison metric.

Sources are drawn from regulators, universities and published research, and each one is labelled with what it actually is — a preprint is not called a paper. Bookmaker and affiliate pages are never cited here, because a page that sells betting is not a neutral authority on it.

Written and maintained by Ellis Warrender, writer and maintainer.

Last updated 28 July 2026. Spotted an error? Tell me and it gets fixed and logged on the corrections page.