{
  "id": "cholesterol",
  "version": "c7687158d427",
  "status": "published",
  "name": "Cholesterol Calculator",
  "question": "What are my cholesterol levels?",
  "summary": "Reads a lipid panel: grades total cholesterol, HDL cholesterol, and triglycerides by NCEP ATP III, and estimates LDL cholesterol with the Sampson (NIH) equation.",
  "category": "health",
  "subcategory": "clinical",
  "url": "https://www.acalculator.org/health/cholesterol-calculator",
  "markdown": "https://www.acalculator.org/health/cholesterol-calculator.md",
  "kind": "function",
  "method": "LDL (Sampson NIH equation 2, mg/dL) = TC/0.948 − HDL/0.971 − (TG/8.56 + TG × non-HDL/2140 − TG²/16100) − 9.44, for TG up to 800. Non-HDL = TC − HDL. Ratio = TC ÷ HDL. Bands: NCEP ATP III.",
  "assumptions": [
    "Total cholesterol, HDL cholesterol, and triglycerides come from the same blood sample.",
    "Each band is read from the whole mg/dL value; SI values are converted with 0.02586 (cholesterol) and 0.0113 (triglycerides) mmol/L per mg/dL first."
  ],
  "inputs": {
    "$schema": "https://json-schema.org/draft/2020-12/schema",
    "type": "object",
    "properties": {
      "units": {
        "title": "Units",
        "description": "US units (mg/dL) or SI units (mmol/L).",
        "type": "string",
        "enum": [
          "us",
          "si"
        ]
      },
      "tc": {
        "title": "Total cholesterol (mg/dL)",
        "description": "Total cholesterol, 50 to 1,000 mg/dL.",
        "type": "number",
        "minimum": 50,
        "maximum": 1000
      },
      "tcSi": {
        "title": "Total cholesterol (mmol/L)",
        "description": "Total cholesterol, 1.3 to 25.9 mmol/L.",
        "type": "number",
        "minimum": 1.3,
        "maximum": 25.9
      },
      "hdl": {
        "title": "HDL cholesterol (mg/dL)",
        "description": "HDL (\"good\") cholesterol, 5 to 200 mg/dL.",
        "type": "number",
        "minimum": 5,
        "maximum": 200
      },
      "hdlSi": {
        "title": "HDL cholesterol (mmol/L)",
        "description": "HDL (\"good\") cholesterol, 0.13 to 5.17 mmol/L.",
        "type": "number",
        "minimum": 0.13,
        "maximum": 5.17
      },
      "tg": {
        "title": "Triglycerides (mg/dL)",
        "description": "Triglycerides, 10 to 3,000 mg/dL.",
        "type": "number",
        "minimum": 10,
        "maximum": 3000
      },
      "tgSi": {
        "title": "Triglycerides (mmol/L)",
        "description": "Triglycerides, 0.11 to 33.9 mmol/L.",
        "type": "number",
        "minimum": 0.11,
        "maximum": 33.9
      }
    }
  },
  "outputs": {
    "ldl": {
      "label": "LDL cholesterol (mg/dL)",
      "description": "LDL cholesterol estimated with the Sampson NIH equation 2, in mg/dL, to a whole number.",
      "format": "number"
    },
    "ldlSi": {
      "label": "LDL cholesterol (mmol/L)",
      "description": "The same estimate in mmol/L (mg/dL × 0.02586), to 2 decimals.",
      "format": "number"
    },
    "ldlCategory": {
      "label": "LDL",
      "description": "The ATP III band of the LDL estimate.",
      "format": "text"
    },
    "tcCategory": {
      "label": "Total cholesterol",
      "description": "The ATP III band of total cholesterol.",
      "format": "text"
    },
    "hdlCategory": {
      "label": "HDL cholesterol",
      "description": "The ATP III band of HDL cholesterol.",
      "format": "text"
    },
    "tgCategory": {
      "label": "Triglycerides",
      "description": "The ATP III band of the triglycerides.",
      "format": "text"
    },
    "nonHdl": {
      "label": "Non-HDL cholesterol (mg/dL)",
      "description": "Total cholesterol minus HDL cholesterol, in mg/dL, to a whole number.",
      "format": "number"
    },
    "ratio": {
      "label": "Total to HDL ratio",
      "description": "Total cholesterol ÷ HDL cholesterol, to 1 decimal.",
      "format": "number"
    }
  },
  "defaultAnswer": {
    "inputs": {
      "units": "us",
      "tc": 200,
      "tcSi": 5.2,
      "hdl": 50,
      "hdlSi": 1.3,
      "tg": 150,
      "tgSi": 1.7
    },
    "outputs": {
      "ldl": 123,
      "ldlSi": 3.19,
      "ldlCategory": "Near or above optimal (100 to 129 mg/dL)",
      "tcCategory": "Borderline high (200 to 239 mg/dL)",
      "hdlCategory": "Between the cut-offs (40 to 59 mg/dL)",
      "tgCategory": "Borderline high (150 to 199 mg/dL)",
      "nonHdl": 150,
      "ratio": 4
    },
    "text": "The estimated LDL cholesterol is 123 mg/dL, Near or above optimal (100 to 129 mg/dL). Total cholesterol: Borderline high (200 to 239 mg/dL). HDL: Between the cut-offs (40 to 59 mg/dL). Triglycerides: Borderline high (150 to 199 mg/dL)."
  },
  "examples": [
    {
      "given": {
        "units": "us",
        "tc": 200,
        "hdl": 50,
        "tg": 150
      },
      "expect": {
        "ldl": 123,
        "ldlSi": 3.19,
        "ldlCategory": "Near or above optimal (100 to 129 mg/dL)",
        "tcCategory": "Borderline high (200 to 239 mg/dL)",
        "hdlCategory": "Between the cut-offs (40 to 59 mg/dL)",
        "tgCategory": "Borderline high (150 to 199 mg/dL)",
        "nonHdl": 150,
        "ratio": 4
      },
      "source": "Sampson 2020 NIH equation 2 = 123.397 mg/dL; ATP III bands for TC 200, HDL 50, TG 150; 200 ÷ 50 = 4.0 (hand calculation in content.mdx)"
    },
    {
      "given": {
        "units": "us",
        "tc": 180,
        "hdl": 60,
        "tg": 100
      },
      "expect": {
        "ldl": 102,
        "ldlCategory": "Near or above optimal (100 to 129 mg/dL)",
        "tcCategory": "Desirable (under 200 mg/dL)",
        "hdlCategory": "High (60 mg/dL or more)",
        "tgCategory": "Normal (under 150 mg/dL)",
        "ratio": 3
      },
      "source": "Sampson 2020 NIH equation 2 = 101.973 mg/dL; ATP III bands (hand calculation in content.mdx)"
    },
    {
      "given": {
        "units": "us",
        "tc": 260,
        "hdl": 35,
        "tg": 500
      },
      "expect": {
        "ldl": 133,
        "tcCategory": "High (240 mg/dL or more)",
        "hdlCategory": "Low (under 40 mg/dL)",
        "tgCategory": "Very high (500 mg/dL or more)",
        "nonHdl": 225,
        "ratio": 7.4
      },
      "source": "Sampson 2020 NIH equation 2 = 133.323 mg/dL; 260 ÷ 35 = 7.43 (hand calculation in content.mdx)"
    },
    {
      "given": {
        "units": "si",
        "tcSi": 5.2,
        "hdlSi": 1.3,
        "tgSi": 1.7
      },
      "expect": {
        "ldl": 124,
        "ldlSi": 3.21,
        "tcCategory": "Borderline high (200 to 239 mg/dL)",
        "tgCategory": "Borderline high (150 to 199 mg/dL)",
        "ratio": 4
      },
      "source": "201.083, 50.271 and 150.442 mg/dL; Sampson 2020 NIH equation 2 = 124.129 mg/dL, × 0.02586 = 3.210 mmol/L (hand calculation in content.mdx)"
    }
  ],
  "sources": [
    "Expert Panel on Detection, Evaluation, and Treatment of High Blood Cholesterol in Adults. Executive summary of the third report of the National Cholesterol Education Program (NCEP) Adult Treatment Panel III. JAMA. 2001;285(19):2486-2497. https://doi.org/10.1001/jama.285.19.2486 (retrieved 2026-10-05)",
    "Sampson M, Ling C, Sun Q, et al. A new equation for calculation of low-density lipoprotein cholesterol in patients with normolipidemia and/or hypertriglyceridemia. JAMA Cardiol. 2020;5(5):540-548. https://doi.org/10.1001/jamacardio.2020.0013 (open at https://pmc.ncbi.nlm.nih.gov/articles/PMC7240357/, retrieved 2026-10-05)",
    "The NIH equation 2 written out in text: Assessing the practical differences in LDL-C estimates calculated by Friedewald, Martin/Hopkins, or NIH equation 2. https://pmc.ncbi.nlm.nih.gov/articles/PMC10548185/ (retrieved 2026-10-05)",
    "Nelson RH. Hyperlipidemia as a risk factor for cardiovascular disease. Prim Care. 2013;40(1):195-211. Table 1 reproduces the ATP III classification of LDL, total, and HDL cholesterol and triglycerides. https://pmc.ncbi.nlm.nih.gov/articles/PMC3572442/ (retrieved 2026-10-05)"
  ],
  "related": [],
  "changelog": [
    {
      "date": "2026-10-05",
      "note": "Published after this site's editorial review against the cited sources (no clinician review); the page notices say so."
    }
  ]
}