📏 Waist-to-Hip Ratio Calculator – Assess Central Fat Distribution
The waist-to-hip ratio (WHR) is one of the most widely used clinical screening tools for evaluating central adiposity — the concentration of body fat around the abdomen. Unlike BMI, which measures overall body mass relative to height, WHR directly captures where fat is stored on the body, making it a strong predictor of cardiometabolic risk.
🔢 Core Formula
WHR = Waist Circumference ÷ Hip CircumferenceBoth measurements must use the same unit before dividing. Because the result is a dimensionless ratio, it is the same whether you measure in centimetres, inches, or millimetres — provided both inputs share the same unit.
⚠️ Sex-Specific Risk Thresholds (WHO Guidance)
WHR risk categories differ between males and females because of natural differences in fat distribution patterns:
| Sex | Low Risk | Moderate Risk | High Risk |
|---|---|---|---|
| Male | WHR < 0.90 | 0.90 – 0.99 | ≥ 1.00 |
| Female | WHR < 0.80 | 0.80 – 0.84 | ≥ 0.85 |
📐 How to Measure Correctly
Accurate inputs lead to a meaningful result. Follow these steps:
- Waist: Locate the midpoint between the bottom of your lowest rib and the top of your hip bone — usually just above the navel. Wrap the tape horizontally, breathe normally, and exhale before reading the measurement.
- Hips: Stand with feet together and measure at the widest point of your buttocks/hips, keeping the tape parallel to the floor.
- Do not pull the tape too tightly — a snug but comfortable fit is correct.
- Measure directly against bare skin or thin clothing for accuracy.
📊 Fat Distribution Patterns
Body fat tends to accumulate in two broad patterns:
- Android (central/apple-shaped): Fat concentrated around the abdomen and waist. Associated with higher cardiometabolic risk. More common in males and post-menopausal females.
- Gynoid (peripheral/pear-shaped): Fat stored around the hips, thighs, and buttocks. Generally associated with lower metabolic risk than central fat.
A higher WHR indicates more android (central) fat distribution. Visceral fat — fat surrounding internal organs — is metabolically active and releases inflammatory compounds that elevate the risk of type 2 diabetes, cardiovascular disease, and metabolic syndrome.
🎯 Goal Planning Mode
If you have a target WHR in mind, the calculator can estimate the waist or hip circumference you would need to achieve it:
Target Waist = Target WHR × Hip Circumference
Target Hip = Waist Circumference ÷ Target WHRThis is useful for setting fitness goals or tracking body composition changes over time by comparing against a previous WHR value.
🔄 WHR vs. Other Body Composition Metrics
- BMI reflects total body mass relative to height but does not distinguish muscle from fat or central from peripheral fat.
- Waist-to-Height Ratio (WHtR) uses a single universal threshold (0.5) but does not account for hip size.
- Body Fat % measures total fat mass but requires specialised equipment for accuracy.
- WHR is quick, equipment-free, and captures fat distribution — making it a complementary tool alongside BMI and WHtR.
⚕️ Important Disclaimer
WHR is a screening metric, not a diagnostic tool. A high or low result should be interpreted in context with other health information. Always consult a qualified healthcare professional for personalised medical advice.