Waist-to-height ratio calculator (WHtR)
Divide waist by height to assess health risk — the simple "keep your waist under half your height" rule.
Rule of thumb: keep your waist below half your height (WHtR < 0.5). A simple, strong indicator of cardiometabolic risk — but not a substitute for medical advice.
How the calculation works
The waist-to-height ratio (WHtR) compares your waist to your height — a quick sign of abdominal fat, the most concerning kind.
WHtR = waist ÷ height (same unit)
Golden rule: keep your waist below half your height (WHtR < 0.5).
Step-by-step example
Waist 80 cm, height 170 cm: 80 ÷ 170 = 0.47 → within healthy range.
Why it often beats BMI
BMI does not separate fat from muscle or say where fat is. WHtR focuses on belly (visceral) fat, linked to diabetes and heart disease. Best used with BMI. It is an estimate — not a medical assessment.
Examples
- Height 180 cm: keep the waist below 90 cm (WHtR 0.5).
- Waist 95 cm, height 165 cm: 0.58 → elevated risk.
Frequently asked questions
WHtR or BMI?
WHtR looks at abdominal fat, tied to more risk. Used alongside BMI, it gives a better picture.
How to measure the waist correctly?
Tape at navel height, relaxed, without holding your breath or tightening. Measure in the morning, fasting, for consistency.
What WHtR is healthy?
Below 0.5 for adults. 0.5–0.6 warrants attention; above 0.6, elevated risk.
What is a healthy waist-to-height ratio?
Between 0.40 and 0.49 — keep your waist under half your height. From 0.50 risk rises.
Where exactly do I measure the waist?
Midway between the lowest rib and the hip bone, tape parallel to the floor, at the end of a normal exhale.
Why is this better than BMI?
Because BMI cannot see fat distribution, and abdominal fat carries much stronger risk associations.
Can my waist shrink without losing weight?
Yes, and it is common when starting strength training — you can lose fat and gain lean mass at once.
Sources and references
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Updated on June 30, 2026 · by Rafael Rossi · Methodology & sources