Guide
What is closing line value?
Closing line value compares the odds you took against the odds available when the market closed. It is the fastest reliable read on whether a selection method is finding something real.
How to calculate it
Take 2.10 and see the market close at 1.95 and you beat the close by 7.7%. Positive CLV across a run of bets means you are consistently ahead of a market that ends up sharper than any individual bettor.
CLV % = (odds_taken / closing_odds − 1) × 100
Why it is more informative than results
Results need hundreds of settled bets before they say much. CLV gives a usable signal after a few dozen, because it measures the decision rather than the outcome. A method with consistently positive CLV and a negative short-run profit is far more likely to be sound than the reverse.
The link to dropping odds
A market that drops after you take a price is the same phenomenon measured from the other end. Getting in before a well-supported move is exactly what produces positive closing line value.