Closing Line Value (CLV): The Most Important Betting Metric

If you're evaluating your sports betting skill by win rate, you're doing it wrong. Professional bettors know that Closing Line Value (CLV) is the only reliable metric that separates skilled bettors from lucky ones. Here's why.

What is Closing Line Value?

Closing Line Value (CLV) measures whether you consistently beat the closing line - the final odds offered before an event begins.

The closing line is significant because it represents the market's most informed estimate of probability. By game time, all available information has been factored in: injury updates, weather changes, sharp money, public betting patterns, and late-breaking news. The line at close is as efficient as it gets.

If you bet a team at -3 and the line closes at -3.5, you got positive CLV. The market moved in your direction, confirming you found value before others did. If you bet at -3 and it closes at -2.5, you got negative CLV. The market thinks you paid too much.

Why CLV Matters More Than Win Rate

Win rate is an unreliable indicator of skill for several reasons:

1. Variance Dominates Short-Term Results

A coin-flipping bettor will have a 50% win rate, but they'll experience wild swings. Over 100 bets at -110 odds, they might win 60 or lose 60 purely from luck. It takes thousands of bets for skill to emerge from variance.

2. Win Rate Doesn't Account for Odds

A 60% win rate on -200 favorites is a losing strategy (you need 66.7% to break even). A 40% win rate on +150 underdogs is profitable (you only need 40% to break even). Win rate without context is meaningless.

3. Lucky Streaks Feel Like Skill

It's impossible to distinguish a good bettor from a lucky one over 100 bets. Only long-term edge proves skill, and long-term means thousands of bets.

CLV solves these problems:

• Every bet generates CLV data, regardless of outcome
• Positive CLV indicates you're finding value the market later confirms
• CLV converges to true skill faster than win rate
• You can evaluate skill with fewer bets

Research shows that bettors with consistent positive CLV are profitable long-term, even if they're running below expected win rate currently. CLV is predictive; past results are not.

How to Calculate CLV

CLV can be calculated in two ways: line-based and odds-based.

Line-Based CLV (Spreads/Totals)

Simply compare your bet price to the closing price:

• Bet: Chiefs -3
• Closing Line: Chiefs -4
• CLV: +1 point

Odds-Based CLV (Any Market)

Convert odds to implied probability and compare:

1. Convert your bet odds to implied probability
2. Convert closing odds to implied probability
3. CLV = Closing Implied Prob - Your Implied Prob

Example:

• You bet: +150 (implied 40%)
• Closing odds: +120 (implied 45.5%)
• CLV = 45.5% - 40% = +5.5%

This 5.5% CLV means you got odds implying a 40% chance when the market eventually said it was closer to 45.5%. You found value.

CLV in Practice

Example 1: Positive CLV, Loss

You bet Bills +3 at -110. The line closes at Bills +1.5. The Bills lose by 2.

• You lost the bet (Bills lost by 2, you had +3)
• Wait, you actually won! Bills +3 covers a 2-point loss
• More importantly: you had +1.5 points of CLV

Even if this bet had lost (say Bills lose by 5), the positive CLV indicates good process. Over time, positive CLV bets win more than negative CLV bets at the same odds.

Example 2: Negative CLV, Win

You bet Patriots -7 at -110. The line closes at Patriots -5. The Patriots win by 8.

• You won the bet (Patriots covered -7)
• But: you had -2 points of CLV

You got lucky. The market moved against you, meaning sharps thought Patriots -7 was a bad bet. You won this time, but making -CLV bets consistently will lose long-term.

Example 3: Tracking CLV Over Time

Imagine tracking 100 bets:

• Average CLV: +1.5%
• Win Rate: 48%

Despite being below 50% wins, this bettor is likely profitable. Their positive CLV indicates they're finding value, and variance has them running cold. Given time, their win rate will likely converge above break-even.

How to Improve Your CLV

1. Bet Early

The earlier you bet, the more opportunity for the line to move in your favor. Opening lines are less efficient than closing lines. Sharps bet early; be like the sharps.

2. Line Shop Aggressively

If one book has Chiefs -3 and another has Chiefs -2.5, always take the -2.5. This half-point matters for CLV and actual win probability.

3. Target Soft Markets

Props, player markets, and smaller games often have less efficient lines. They're more likely to move after you bet, generating CLV.

4. Follow Sharp Action

If you're consistently betting with sharp money, you'll naturally generate positive CLV because sharps move lines. Learn about sharp money.

5. Avoid Steam Chasing

Betting after lines have already moved toward your side gives you negative CLV. If the line has moved 2 points in your direction, the value is already gone.

Tracking CLV with Prop Monkey

Tracking CLV manually is tedious. You'd need to record every bet's odds, then check closing lines for each one. Over hundreds of bets, this becomes a significant burden.

Prop Monkey automates CLV tracking for you:

Automatic Closing Line Capture

We record the closing odds for every market, so you can always compare your bet price to where the line closed.

CLV Dashboard

See your average CLV across all bets, broken down by sport, market type, and time period. Identify where you're finding the most value and where you might be making mistakes.

Early Value Alerts

We notify you of line value as soon as we detect it, helping you bet early when CLV opportunity is highest. The sooner you act on our picks, the more CLV you'll capture.

Expected Value Picks

Beyond tracking your CLV, we surface bets that are likely to generate positive CLV based on our analysis. We calculate edge before the market has fully adjusted, giving you first-mover advantage.

Key Takeaways

• Closing Line Value (CLV) measures how your bet price compares to the closing line
• CLV is a better predictor of long-term success than win rate
• Positive CLV means the market moved in your direction, confirming value
• Bet early and line shop to maximize CLV
• Track CLV over time to truly evaluate your betting skill

Now that you understand CLV, learn how to properly size your bets with the Kelly Criterion.