{
  "slug": "waist-to-hip-ratio",
  "title": "Waist-to-Hip Ratio Calculator",
  "category": "Body Composition",
  "category_slug": "body-composition",
  "tier": 2,
  "summary": "Calculate waist-to-hip ratio (WHR) from two tape measurements using the WHO measurement protocol.",
  "description": "This calculator computes waist-to-hip ratio (WHR) by dividing waist circumference by hip circumference, both in centimetres. WHR is one of the oldest tape-based body-shape indices in the epidemiological literature and is the subject of a dedicated WHO expert consultation, which standardised how both measurements are taken and tabulated reference thresholds of 0.90 for men and 0.85 for women. The tool returns the ratio to two decimal places alongside those published thresholds, presented as reference points from the WHO report rather than as an assessment of any individual.",
  "page_url": "https://fitmetriclab.com/en/tools/body-composition/waist-to-hip-ratio/",
  "api_url": "https://fitmetriclab.com/api/tools/waist-to-hip-ratio.json",
  "formula": {
    "id": "waist_to_hip_ratio",
    "expression": "\\text{WHR} = \\frac{w}{h_{hip}}",
    "variables": [
      {
        "symbol": "w",
        "description": "Waist circumference in cm"
      },
      {
        "symbol": "h_{hip}",
        "description": "Hip circumference in cm"
      }
    ]
  },
  "inputs": [
    {
      "id": "waist_cm",
      "label": "Waist Circumference",
      "type": "number",
      "unit": "cm",
      "default": 85,
      "min": 40,
      "max": 200,
      "step": 0.5
    },
    {
      "id": "hip_cm",
      "label": "Hip Circumference",
      "type": "number",
      "unit": "cm",
      "default": 100,
      "min": 50,
      "max": 200,
      "step": 0.5
    }
  ],
  "worked_example": {
    "inputs": {
      "waist_cm": 85,
      "hip_cm": 100
    },
    "expected_output": "0.85"
  },
  "result_summary_template": "With a waist of {waist_cm} cm and hips of {hip_cm} cm, the waist-to-hip ratio works out to {result}.",
  "methodology": "Waist-to-hip ratio = waist circumference (cm) ÷ hip circumference (cm), reported to two decimal places. Measurements follow the WHO expert consultation protocol: waist at the midpoint between the last palpable rib and the iliac crest at the end of normal exhalation; hip around the widest portion of the buttocks with the tape parallel to the floor. The displayed thresholds (0.90 men, 0.85 women) are the reference cut-points tabulated in the WHO consultation report; the report notes that appropriate cut-points vary across populations.",
  "sources": [
    {
      "label": "World Health Organization. Waist circumference and waist-hip ratio: report of a WHO expert consultation. Geneva, 2008 (published 2011).",
      "url": "https://www.who.int/publications/i/item/9789241501491"
    },
    {
      "label": "World Health Organization. Physical status: the use and interpretation of anthropometry. WHO Technical Report Series 854. 1995.",
      "url": "https://www.who.int/publications/i/item/9241208546"
    }
  ],
  "faqs": [
    {
      "question": "How does the WHO protocol say the two measurements are taken?",
      "answer": "Waist: tape at the midpoint between the lower margin of the last palpable rib and the top of the iliac crest, horizontal, snug without compressing the skin, read at the end of a normal exhalation. Hip: tape around the widest portion of the buttocks, parallel to the floor. The subject stands with feet together and arms relaxed, and each girth is measured twice — with both repeated if the pair differs by more than 1 cm. The consultation standardised this because studies using different landmarks produced ratios that were not comparable with each other."
    },
    {
      "question": "Can the ratio stay the same while both measurements change?",
      "answer": "Yes, and this is the index's defining property. Adding 4 cm to an 85 cm waist and 4 cm to 100 cm hips moves the ratio from 0.85 to about 0.856 — nearly invisible at two decimal places, despite 8 cm of combined change. The division preserves proportion and discards size. For tracking change over time, recording the two raw circumferences alongside the ratio retains the information the division throws away; the ratio alone cannot reveal which of its two inputs moved, or in which direction."
    },
    {
      "question": "How is WHR different from waist-to-height ratio?",
      "answer": "The numerator is the same; the denominator changes what the index describes. Dividing by hip circumference compares two soft-tissue girths, so WHR measures torso shape and moves when either girth changes. Dividing by height compares a girth against a fixed skeletal dimension, so waist-to-height ratio tracks abdominal girth against a denominator that adulthood holds constant. The WHO consultation reviewed both conventions and noted they perform differently across study populations; the two calculators on this site let the same tape measurements be viewed through both lenses."
    },
    {
      "question": "Does clothing or timing affect the measurements?",
      "answer": "Both, by amounts that matter at two decimal places. The WHO protocol specifies measurement over bare skin or light clothing, since waistbands add centimetres unevenly. Waist circumference also varies through the day — food, fluid, and posture move it by 1–2 cm between morning and evening — while hip circumference is comparatively stable, so timing shifts the ratio asymmetrically. Measuring at a consistent time, over consistent clothing, with the same tape tension keeps a series comparable; a single reading taken casually carries an uncertainty of roughly ±0.02 on the ratio."
    },
    {
      "question": "What do the 0.90 and 0.85 thresholds represent?",
      "answer": "They are the reference cut-points the WHO expert consultation tabulated for men and women when reviewing the population studies available to it — values used to classify participants in that research. The report itself notes that suitable cut-points differ across populations and by ancestry, and that measurement conventions varied between the underlying studies. This calculator displays the thresholds as published context from the report, alongside the computed ratio. Whether a given value sits above or below one of them is a fact about two tape measurements, not an evaluation of the person holding the tape."
    }
  ],
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      "api_url": "https://fitmetriclab.com/api/tools/waist-to-height-ratio.json",
      "page_url": "https://fitmetriclab.com/en/tools/body-composition/waist-to-height-ratio/"
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  ],
  "last_updated": "2026-08-08",
  "price": {
    "value": 0,
    "currency": "USD"
  },
  "runs_in_browser": true,
  "disclaimer": "Educational estimate produced from a published formula. Not medical, nutritional, or training advice. Calculations are deterministic — apply the formula to the inputs to reproduce the result."
}