{
  "slug": "closing-line-value-calculator",
  "title": "Closing Line Value (CLV) Calculator",
  "heading": "Closing Line Value Calculator",
  "category": "math",
  "url": "https://www.revenuelab.fyi/toolbox/closing-line-value-calculator",
  "summary": "Measure whether you beat the market's final price, independent of the result.",
  "description": "Closing line value compares the odds you bet at against the market's closing odds right before the event starts — widely regarded by sharp bettors and market researchers as the single best predictor of long-run betting profitability, better than short-term win-loss record. The closing line is treated as the market's most efficient, information-complete price, so consistently beating it (getting a better number than what the market settles on) suggests real skill or good timing, even across a stretch where results run bad from variance. This calculator takes your bet's odds and the closing odds on the same side, converts both to implied probability, and reports the gap in percentage points and in 'cents' (a common bettor shorthand for basis-point-like odds movement). Positive CLV over a large sample is a strong signal you're finding value; negative CLV over a large sample, even with a winning record, often means you're getting lucky rather than skilled, because closing lines tend to be more accurate on average than opening or midweek lines.",
  "formula": "CLV (probability) = implied probability at closing line − implied probability at your bet. Positive CLV means you got a bet placed at better odds (lower implied probability) than the closing number.",
  "dateModified": "2026-09-30",
  "run_url": "https://www.revenuelab.fyi/api/public/calc?tool=closing-line-value-calculator",
  "inputs": [
    {
      "id": "yourOdds",
      "label": "Odds you bet at (American)",
      "kind": "number",
      "hint": null,
      "default": -105,
      "unit": null,
      "min": null,
      "max": null
    },
    {
      "id": "closingOdds",
      "label": "Closing odds, same side (American)",
      "kind": "number",
      "hint": null,
      "default": -125,
      "unit": null,
      "min": null,
      "max": null
    }
  ],
  "outputs": [
    {
      "id": "clv",
      "label": "Closing line value (percentage points)",
      "format": "percent",
      "hint": null,
      "primary": true
    },
    {
      "id": "yourImplied",
      "label": "Your bet's implied probability",
      "format": "percent",
      "hint": null,
      "primary": false
    },
    {
      "id": "closingImplied",
      "label": "Closing line implied probability",
      "format": "percent",
      "hint": null,
      "primary": false
    },
    {
      "id": "clvPercentOdds",
      "label": "CLV as % better price (decimal odds)",
      "format": "percent",
      "hint": null,
      "primary": false
    }
  ],
  "worked_example": {
    "inputs": [
      "Odds you bet at (American): -105",
      "Closing odds, same side (American): -125"
    ],
    "outputs": [
      "Closing line value (percentage points): 4.34%",
      "Your bet's implied probability: 51.22%",
      "Closing line implied probability: 55.56%",
      "CLV as % better price (decimal odds): 8.47%"
    ]
  },
  "how_to": {
    "title": "How to use this",
    "steps": [
      "Enter odds you bet at (american).",
      "Enter closing odds, same side (american).",
      "Read your closing line value (percentage points) on the right — it updates as you type.",
      "Hit Share to keep the scenario or send it to someone."
    ]
  },
  "scenarios": [
    {
      "name": "Conservative",
      "description": "Lower-end numbers — what if things land soft?",
      "values": {
        "yourOdds": -65,
        "closingOdds": -75
      }
    },
    {
      "name": "Typical",
      "description": "Defaults — the most common real-world setup.",
      "values": {
        "yourOdds": -105,
        "closingOdds": -125
      }
    },
    {
      "name": "Ambitious",
      "description": "Higher-end numbers — what if things really pop?",
      "values": {
        "yourOdds": -170,
        "closingOdds": -200
      }
    }
  ],
  "limitations": [
    "Results are rounded for display; the underlying calculation keeps full precision.",
    "Very large or very small inputs may hit floating-point limits in the browser.",
    "Inputs outside the accepted range are clamped rather than rejected."
  ],
  "faq": [
    {
      "q": "Why is CLV considered more predictive than my actual win-loss record?",
      "a": "Win-loss records over any realistic sample size (dozens to low hundreds of bets) are heavily influenced by variance — a skilled bettor can run bad for months and an unskilled one can run hot. CLV strips out that noise because it measures your price relative to the market's most efficient number at every single bet, giving a much faster and more stable read on whether you're finding real value."
    },
    {
      "q": "What counts as good CLV?",
      "a": "Consistently beating the closing line by even 1-2% in implied probability across a large sample is considered a strong, sustainable signal in sharp betting circles. Beating it by 3%+ regularly is rare and typically associated with serious modeling or very fast execution on line moves — most casual bettors, even disciplined ones, hover near breakeven CLV or slightly negative."
    },
    {
      "q": "Can I have negative CLV but still be a long-run winning bettor?",
      "a": "It's possible over a small sample, but it's a warning sign over a large one. If the closing line consistently prices your bets as worse than your entry price, on average, it suggests you're getting favorable results despite the market disagreeing with your timing, which historically tends to regress rather than persist."
    },
    {
      "q": "Does CLV apply to fantasy or futures bets the same way?",
      "a": "The same logic applies to any market with a clear closing price — futures, season win totals, and player props all technically have a 'closing' number, though liquidity and how often the number moves varies a lot more than in game lines. CLV is most reliable and most commonly tracked on frequently-traded game lines like spreads, totals, and moneylines."
    }
  ],
  "related": [
    "https://www.revenuelab.fyi/toolbox/no-vig-fair-odds",
    "https://www.revenuelab.fyi/toolbox/expected-value-bet-calculator",
    "https://www.revenuelab.fyi/toolbox/line-shopping-value-calculator"
  ],
  "license": "CC-BY-4.0",
  "citation": "RevenueLab — Closing Line Value (CLV) Calculator (https://www.revenuelab.fyi/toolbox/closing-line-value-calculator)"
}