Sports Betting 101
intermediate9 min read
Understanding Closing Line Value: The #1 Predictor of Betting Success
Why the odds you get matter more than whether you win or lose — and how to track the metric that separates sharps from squares.
What is Closing Line Value?
Closing Line Value (CLV) measures whether the odds you bet at were better than the final odds before the event started. It's the single best predictor of long-term betting profitability.
Why CLV Matters More Than Win Rate
Here's a counterintuitive truth: a bettor who consistently beats the closing line will be profitable long-term, even if their short-term record looks mediocre. Conversely, a bettor with a 60% win rate who consistently gets worse odds than the close is likely on a lucky streak that won't last.
How to Calculate CLV
Simple Method
- Record the odds when you place your bet
- Record the closing odds (just before game time)
- Compare: Did you get a better number?
Example
- You bet: Chiefs -3 (-110) on Monday
- Closing line: Chiefs -4.5 (-110)
- You got +1.5 points of CLV — excellent
No-Vig Method (More Accurate)
- Convert closing odds to no-vig probabilities
- Compare your bet odds to the no-vig close
- The difference is your true CLV
What Good CLV Looks Like
| CLV | Assessment |
|---|---|
| Consistently negative | Losing long-term |
| Around zero | Breaking even |
| +1 to +3% | Good, sustainable edge |
| +3 to +5% | Very strong |
| +5%+ | Elite (or small sample) |
How to Improve Your CLV
- Bet early — Lines are least efficient when first posted
- Line shop — Best odds = better CLV
- Build models — Independent analysis finds value before the market corrects
- Follow sharp indicators — Reverse line movement, steam moves
The Bottom Line
Track your CLV religiously. Over 500+ bets, it tells you whether you have a genuine edge or are just running hot.