Closing Line Value and Why Odds Move
Of all the ways to judge whether a bettor has an edge, beating the closing line is the one professionals trust most, because it does not wait for results. This guide explains what the closing line is, why it is hard to beat, and how to measure it for yourself.
What the closing line is
Odds move from the moment a market opens until the match starts. The last price available before kick-off is the closing line. By then every piece of news, every lineup, and every large bet has been absorbed into the price, so the closing line is the market's best estimate of the true probability. Study after study of bookmaker data finds that closing prices predict results more accurately than opening prices, and more accurately than almost any individual forecaster.
Why odds move
Three things move a price. Money: when a lot is staked on one side, the bookmaker shortens it to balance the book and lengthens the other. Information: a late injury, a changed lineup, weather, or a sharp bettor's action that the book treats as information in itself. And copying: most books follow the lead of one or two market-makers, so a move at the sharpest book ripples across the others within minutes.
A price that shortens between publication and kick-off is one the market came to agree with. A price that drifts is one the market moved against. Neither tells you the result; both tell you something about the quality of the price you took.
How to measure it
Convert both prices to implied probability by dividing 1 by the decimal odds. Subtract the probability at the price you took from the probability at the close. Backing a side at 2.10 (47.6%) that closes at 1.90 (52.6%) is +5.0 points of closing line value. Backing at 1.90 and watching it drift to 2.10 is −5.0 points. Average the figure over every bet. A bettor whose average is positive over several hundred bets is, with high confidence, taking better prices than the market offers at kick-off, and will be profitable in the long run whatever the recent results say.
A fairer version removes the bookmaker's margin first, by scaling the implied probabilities of all outcomes so they sum to 100%, but the simple version is enough to see the sign and the trend.
What it can and cannot tell you
Closing line value is a measure of price, not of results. It is the better measure over a short period, because results are noisy and prices are not: a hundred bets can show a profit or a loss by luck, but a hundred bets that each beat the close by three points are not luck. It is the weaker measure of what actually happened, which is what a record is for. The two belong together: results show what was won, CLV shows whether it was won at prices the market later agreed were too good.
It also assumes the closing line is efficient, which is truer of the Premier League or an NFL game, where the markets are deep, than of a second-tier tennis match or a minor league, where the closing price can be as uninformed as the opening one. In thin markets, beating the close means less.
How this applies to the record
Every tip on this site is graded at the price recorded when it was published, which is the price shown on the tip's page. Closing prices are not stored, so the record shows results, strike rate and return rather than closing line value. Anyone following a tip can measure their own by noting the price at kick-off against the one on the page. The expected value guide covers what the record itself can show, and the odds ranges guide measures the gap between implied and actual strike rate, which is the nearest thing to CLV a results record can offer.
Prices move after publication in both directions, so a follower may get a better or worse price than the one recorded. The track record is graded at the published price in every case.
Frequently asked questions
What is closing line value?
The difference between the price you took and the price available when the market closed at kick-off, measured in implied probability. If you backed a side at 2.10 and it closed at 1.90, you beat the closing line by about 5 points of implied probability. Over many bets, consistently beating the close is the strongest evidence of an edge that exists, because the closing price carries all the money and information the market has.
Does Clarity Tip publish closing odds?
No. Each tip page shows the price recorded when the tip was published, and the record is graded at that price. Closing prices are not stored, so the record cannot show closing line value directly. Anyone following a tip can measure their own CLV by noting the price at kick-off.
Can a bet beat the closing line and still lose?
Constantly. Beating the close says the price you took was better than the market's final estimate, not that the selection wins. A bettor who beats the close by 3 points on average will still lose roughly as often as the odds say; they will simply be paid more than they should be when they win.
More guides
- Which Odds Ranges Win Most Often · Strike rate and return for every price band in the record, against what the odds implied.
- Results by Betting Market · Match winner, totals, handicaps, both teams to score and props: how each market has performed.
- How Long Losing Runs Last · The longest winning and losing runs in the record, the biggest drawdown, and what that means for a bankroll.
- Expected Value in Betting, Explained · What a positive expected value bet is, how implied probability works, and how to read it off a real record.
- Staking Plans: Flat, Percentage and Kelly · How the main staking methods behave through a losing run, with the record's own drawdown as the test case.
- All guides and monthly results
18+ only. Please gamble responsibly. Past results do not guarantee future outcomes. Figures on this page are recomputed from the public record as tips settle.