Closing line value on prediction markets: the best test of a bet
Closing line value (CLV) is the closing price minus the price you paid. Buy a team at 45¢ that closes at 50¢ and you got 5¢ of CLV. Over many bets, beating the close is the clearest sign you are getting good prices.
Key takeaways
- CLV = closing price − your price, in cents, for the side you bought.
- Results are noisy over a season; CLV shows whether you beat the market long before results do.
- Exchanges make CLV easy to measure because the price history is public.
- Sports Index grades every strategy pick by CLV as well as wins and losses.
Winning a bet tells you the outcome went your way. It doesn't tell you whether the bet was good. Closing line value does, and prediction markets make it unusually easy to measure.
What is closing line value?
The closing line is the last price before a game starts, when the market has absorbed all the news and the most money. Closing line value (CLV) is the difference between that price and the one you paid:
- You buy a team at 45¢. It closes at 50¢. You got +5¢ of CLV: the market moved toward your side.
- You buy at 45¢ and it closes at 41¢. That's −4¢: you paid more than the market's final view.
Why is CLV a better test than winning?
A season of college football bets is a small sample, and any one result is close to a coin flip. A bettor with a real edge can lose for weeks, and a bad bettor can get lucky. CLV is measured on every bet the moment the game kicks off, so it shows whether you are buying good prices long before your record settles down.
The closing price on a busy market is a hard number to beat because thousands of traders have had their say. If you beat it consistently, you are getting prices the market later agreed were too cheap.
How do you measure CLV on an exchange?
- Record the price you paid for each position (after fees, if you want to be strict).
- Record the price of the same contract just before kickoff.
- Subtract: closing price − your price. Average it across all your bets.
On a sportsbook, the closing line includes the book's margin, which muddies the comparison. On an exchange, the closing price is a traded price, so it is a cleaner benchmark. Sports Index records both exchanges' prices through every college football game, so the close is always on hand.
Which strategies beat the close?
Every Sports Index strategy pick is graded on closing-line value as well as wins and losses. This chart shows each strategy's average CLV per bet across its settled picks; strategies with only a handful of graded closes are left out.
Sports Index
See the data
| Strategy | Average CLV | Settled bets |
|---|---|---|
| Low total overs | +0.2¢ | 14 |
| High total unders | -0.1¢ | 6 |
| Pro strategies (combined) | -0.3¢ | 54 |
| Big home dogs | -1.3¢ | 13 |
See college football strategies, tested for each strategy's rule and full record.
What is a good CLV?
- Consistently positive is the goal. A 1–2¢ average edge over hundreds of bets is strong.
- Around zero means you are paying fair prices: your results will mostly reflect luck, minus fees.
- Consistently negative means you are buying after the market has moved. Try placing bets earlier or with limit orders, and compare both exchanges first.
Frequently asked questions
What is a good closing line value?
Any consistent positive average is good. A bettor who beats the close by 1–2¢ on average across hundreds of bets is getting better prices than the market's final view.
Does positive CLV guarantee profit?
No. It means you bought at better prices than the market's final estimate. Over a large sample that tends to show up as profit, but any single bet can lose.
How is CLV different on exchanges and sportsbooks?
The idea is the same. On an exchange the closing price is a traded price with no sportsbook margin in it, so it is a cleaner benchmark.
Sources
Facts that change, such as fees, rules and where each exchange operates, were checked on the date above. Check the exchange's own pages before you trade.
Sports Index Markets Every college football price in one place Novig and Kalshi side by side, with price history, strategies with graded records and the twice-weekly Betting Roundup. Open Markets →Keep reading
College football betting strategies, testedWhich college football betting systems work on prediction markets? Rule-based strategies graded on real Kalshi and Novig prices.
Line shopping between Kalshi and NovigHow often Kalshi and Novig price the same game differently, what a better price is worth after fees, and how to shop both before you trade.
How to read prediction market oddsA prediction market price in cents is an implied probability. Convert any price to American odds and payout with our table, converter and examples.
Sports Index publishes research and paper picks; it is not a sportsbook or an exchange and takes no bets. Trading on prediction markets risks real money. You must meet the exchange's age requirement and be in an eligible state. If gambling is a problem for you or someone you know, call or text 1-800-GAMBLER.