Waist-to-Hip Ratio,
your WHO health risk score.

Field guide

What WHR tells you that BMI cannot.

Your waist-to-hip ratio (WHR) is one of the simplest and most clinically validated ways to assess whether your fat distribution poses a health risk. Unlike Body Mass Index (BMI), which only considers your total weight relative to height, WHR tells you where your body stores fat — and location matters enormously for cardiovascular health.

The formula

WHR is calculated by dividing your waist circumference by your hip circumference. Both measurements must be in the same unit (centimetres or inches) — the unit cancels out in the division.

For example, a waist of 86 cm and hips of 100 cm gives a WHR of 0.86. A waist of 34 inches and hips of 38 inches gives 0.895.

How to measure correctly

Accurate measurements are essential. Follow these guidelines:

• Waist: Measure at the narrowest point of your torso, usually halfway between the bottom of your ribcage and the top of your hip bone. Stand relaxed with feet together; breathe normally and measure at the end of a gentle exhale.
• Hips: Measure at the widest point of your hips and buttocks, usually about 7–9 inches (18–23 cm) below your natural waist. Keep the tape parallel to the floor and snug but not compressing the skin.
• Use a flexible (not stretchy) measuring tape. Avoid measuring over bulky clothing. Repeat twice and use the average.

WHO health risk categories

The World Health Organization classifies WHR into four health risk levels. The thresholds differ by sex because women naturally carry more fat around the hips and thighs.

• Low risk: Men <0.90, Women <0.80. Fat is predominantly stored in the hips and thighs (gynoid distribution). Cardiovascular risk from fat distribution is minimal.
• Moderate risk: Men 0.90–0.95, Women 0.80–0.85. Transitional zone. Abdominal fat is accumulating but has not reached levels associated with significantly elevated disease risk.
• High risk: Men 0.96–0.99, Women 0.86–0.89. Central (abdominal) adiposity is present. Associated with increased risk of type 2 diabetes, hypertension, and coronary artery disease.
• Very high risk: Men ≥1.00, Women ≥0.90. Strongly elevated cardiovascular and metabolic risk. Clinical intervention is typically recommended.

Body shape classifications

WHR correlates with body shape, which has its own implications for health and lifestyle:

• Hourglass (Women, WHR ≤0.70): Waist is significantly narrower than hips. Lowest cardiovascular risk from fat distribution. Associated with a gynoid fat pattern.
• Pear (Gynoid): Fat stored preferentially in the hips, thighs, and buttocks. Common in women. Generally lower cardiovascular risk than android (apple) shape.
• Rectangle: Waist and hips are similar in measurement. Transitional shape. Moderate WHR zone.
• Apple (Android): Fat stored predominantly in the abdomen. Higher WHR. Associated with elevated metabolic and cardiovascular risk. More common in men and postmenopausal women.

WHR vs. BMI: which is better?

Both metrics have clinical value, but they measure different things. BMI is easy to calculate and correlates broadly with overall adiposity, but it is blind to fat distribution. A muscular athlete may have a high BMI with low body fat. An older adult may have a normal BMI but carry excess visceral abdominal fat that elevates cardiovascular risk.

Multiple large population studies — including the INTERHEART study (52 countries, 27,000 participants) — found that WHR is a stronger predictor of myocardial infarction (heart attack) risk than BMI. The American Heart Association recognises waist circumference and waist-to-hip ratio as important cardiometabolic risk markers alongside traditional lipid panels.

Ideally, use WHR and BMI together. A person with a normal BMI but elevated WHR still warrants cardiovascular monitoring. A high BMI person with a low WHR (pear-shaped) may face fewer metabolic consequences than their weight alone suggests.

What causes a high WHR?

Abdominal fat accumulation is driven by several overlapping factors:

• Diet: High intake of refined carbohydrates, sugar, and ultra-processed food promotes visceral fat storage.
• Physical inactivity: Sedentary behaviour reduces the body's ability to oxidise abdominal fat. Aerobic exercise specifically targets visceral fat reduction.
• Chronic stress: Cortisol, the primary stress hormone, promotes visceral fat deposition — particularly around the abdomen.
• Poor sleep: Short sleep duration and sleep apnoea are both linked to abdominal adiposity via hormonal dysregulation (ghrelin, leptin, insulin).
• Genetics and hormones: Fat distribution is partly hereditary. Oestrogen promotes gluteal-femoral (pear) fat storage; reduced oestrogen after menopause shifts distribution toward abdominal (apple) fat in women.

How to lower your WHR

Reducing WHR requires reducing waist circumference, which means reducing visceral and subcutaneous abdominal fat:

• Prioritise aerobic exercise — 150–300 minutes per week of moderate-intensity activity (walking, cycling, swimming) has the strongest evidence base for visceral fat reduction.
• Replace refined carbohydrates with fibre-rich whole foods. A Mediterranean-style diet has strong evidence for reducing cardiovascular risk and waist circumference.
• Strength training preserves muscle while reducing fat, improving body composition even when scale weight changes little.
• Manage sleep quality. Target 7–9 hours per night. Address sleep apnoea if present — treatment alone can reduce abdominal fat significantly.
• Reduce chronic stress through regular movement, adequate rest, and mindfulness practices that lower cortisol.

Limitations of WHR

WHR is a useful screening tool but has limitations. It does not distinguish between visceral fat (metabolically active, inside the abdominal cavity) and subcutaneous fat (under the skin, less dangerous). Waist circumference alone can sometimes be a more practical clinical marker. Pregnancy, bloating, and posture can affect measurements. For clinical decision-making, WHR should be interpreted alongside blood pressure, fasting glucose, lipid panel, and medical history.

Disclaimer

This calculator is for educational and informational purposes only. It does not constitute medical advice, diagnosis, or treatment. WHR thresholds are general population guidelines from the WHO; your individual health risk depends on many additional factors. Do not use this tool to self-diagnose a health condition. Always consult a qualified healthcare professional for personalised medical guidance and before starting any diet, exercise, or health-management programme.