Short-term betting results are noisy. A bettor can make good bets and lose, or make poor bets and win over a small sample. Closing Line Value, usually shortened to CLV, is one way to check whether the price you took was better than the market price at close.
This CLV Calculator compares your odds against the closing line. It can run a simple odds-to-closing comparison, or a no-vig version that removes bookmaker margin from the closing market before estimating the fair price.
Important: positive CLV is a strong signal that you are regularly beating the market price, but it is not a guarantee of profit by itself. Sample size, market quality, limits, timing, commission, stale lines and no-vig assumptions all matter.
CLV Calculator
Compare odds taken with closing odds, no-vig fair price and implied probability gap.
How to Use the CLV Calculator
- Enter odds taken: the decimal odds you actually bet, such as 2.10.
- Enter closing odds: the final market odds close to match start, such as 1.95.
- Choose calculation mode: use Simple CLV for a quick check, or No-Vig CLV for a cleaner fair-price estimate.
- For No-Vig mode: enter the closing odds for all outcomes in the market, such as both sides of a two-way market or home/draw/away in football.
- Read the result: positive CLV means the price you took was better than the closing fair estimate. Negative CLV means the market closed at a better price than your entry.
For pre-match research, use the Football Match Analysis Calculator. For live market movement, use the Live Betting Tools. To remove bookmaker margin from a market directly, use the No-Vig Calculator.
What Closing Line Value Means
CLV measures whether you beat the final market price. If you bet 2.20 and the same selection closes at 2.00, you took a better number than the closing market. If you bet 1.80 and the market closes at 1.95, you took a worse number.
The closing line is often treated as a useful benchmark because it reflects more information than the early line: team news, injuries, liquidity, professional action and market correction. It is not perfect, but in liquid markets it is usually a better benchmark than the opening price.
Simple CLV Formula
The simple version compares your odds directly with the closing odds:
Simple CLV = (Odds Taken ÷ Closing Odds) – 1
| Odds Taken | Closing Odds | Simple CLV | Interpretation |
|---|---|---|---|
| 2.20 | 2.00 | +10.00% | You beat the closing price. |
| 2.00 | 2.00 | 0.00% | You matched the closing price. |
| 1.80 | 1.90 | -5.26% | You took a worse price than close. |
Simple CLV is fast, but it treats the closing odds as if they were fair. In reality, bookmaker odds include margin.
Why No-Vig CLV Is More Accurate
No-vig CLV removes bookmaker margin from the closing market first. This gives a cleaner estimate of the closing fair price.
For a two-way market:
- Convert both closing odds to implied probabilities.
- Add the probabilities to get market overround.
- Divide your selection’s implied probability by the overround.
- Convert that normalized probability back into fair odds.
- Compare your odds taken with the no-vig fair price.
This matters because a closing price of 2.00 in a vigged market may not represent a true 50% chance. The fair price can be higher after margin is removed.
Worked Example: Positive CLV
Suppose you bet $100 at 2.20. By kickoff, the market closes at 2.00.
- Odds taken: 2.20
- Closing odds: 2.00
- Simple CLV: (2.20 ÷ 2.00) – 1 = +10.00%
This means you took a better price than the closing market. The bet can still lose, but the entry price was favorable relative to the final market.
Worked Example: Negative CLV
Suppose you bet 1.80 and the market closes at 1.90.
- Odds taken: 1.80
- Closing odds: 1.90
- Simple CLV: (1.80 ÷ 1.90) – 1 = -5.26%
You did not beat the close. Even if the bet wins, this is a warning sign if it happens repeatedly across a large sample.
CLV vs Actual Profit
CLV and profit are related, but they are not the same thing.
| Metric | What it measures | Main weakness |
|---|---|---|
| CLV | Whether your price beat the closing market. | Needs many bets and a reliable closing market. |
| ROI | Actual profit or loss relative to stake. | Can be distorted by short-term variance. |
| Win rate | How often bets win. | Ignores odds and payout size. |
| No-vig edge | Your price compared with a margin-removed fair estimate. | Depends on correct market inputs and assumptions. |
A bettor with positive CLV can still lose money over a small sample. A bettor with negative CLV can still win for a while through variance. Over larger samples, CLV becomes more useful.
How Much CLV Is Good?
There is no universal threshold. It depends on market liquidity, sport, bet type and whether the closing price is a strong benchmark.
| Average CLV | Possible interpretation |
|---|---|
| Negative | You are often taking worse prices than the market close. |
| 0% to +1% | Slightly positive, but may not overcome noise, limits or measurement issues. |
| +1% to +3% | Promising if sustained over a meaningful sample. |
| +3% to +5%+ | Strong signal in liquid markets, but still needs sample-size confirmation. |
Be cautious with tiny samples. Twenty bets are not enough to prove a betting edge. Hundreds or thousands of tracked bets are more useful.
Common CLV Mistakes
- Using the wrong closing line: compare against a real close from the same market type, not a stale or low-liquidity copy.
- Ignoring vig: simple CLV is useful, but no-vig CLV is cleaner.
- Mixing markets: player props, low-tier leagues and limits can behave differently from major football or NFL markets.
- Assuming CLV guarantees profit: it is an indicator, not a payout guarantee.
- Tracking only winners: every bet must be logged, including losses and voids.
Related Betting Tools
- No-Vig Calculator — remove bookmaker margin from a two-way market.
- Bookmaker Margin Calculator — calculate overround across multiple outcomes.
- Odds to Implied Probability Calculator — convert odds into break-even probability.
- Probability to Odds Calculator — convert your estimated chance into fair odds.
- Kelly Criterion Calculator — calculate stake size from edge and bankroll.
Frequently Asked Questions
What is CLV in sports betting?
CLV stands for closing line value. It measures whether the odds you took were better or worse than the final market price before the event started.
How do you calculate CLV?
A simple formula is odds taken divided by closing odds, minus 1. For example, 2.20 taken versus a 2.00 close gives +10% simple CLV.
Why should I use no-vig CLV?
No-vig CLV removes bookmaker margin from the closing market before estimating the fair price. This gives a cleaner comparison than using raw closing odds alone.
Can I have positive CLV and still lose money?
Yes. Short-term betting results are affected by variance. Positive CLV is more meaningful over a large tracked sample.
Does CLV work for prop bets?
It can, but prop markets are often less liquid and move less efficiently than major moneyline, spread or total markets. The closing line may be a weaker benchmark.
Is CLV the same as expected ROI?
No. CLV compares your price with the closing market. Expected ROI estimates theoretical edge from a fair probability. They are related, but not identical.
Responsible gambling notice: CLV analysis can help evaluate price quality, but it does not remove betting risk. Track results honestly, use strict bankroll limits and never bet more than you can afford to lose.