A 1-inch error moves most adults across a risk category. The WHO published a simple protocol — follow it and your number is reliable.
Stand relaxed, feet together, arms at sides. Find the top of your hip bone and the bottom of your ribs. The waist measurement is the midpoint — usually near the belly button.
Exhale normally (don't suck in), keep the tape parallel to the floor, and take the reading at the end of a normal exhalation.
Measuring over thick clothing (adds 0.5–1 inch). Pulling the tape too tight. Measuring after a meal (add 1 inch).
Feed the number into the ratio that matters.
WHtR Calculator →
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