How to measure
Use a soft tape measure, keep it level and snug without pressing into the skin, and stand relaxed: don't breathe in or hold your stomach in.
- Neck: just below your Adam's apple, with the tape sloping slightly down towards the front.
- Waist (men): around your belly button.
- Waist (women): at the narrowest point, usually just above the belly button.
- Hips (women): around the widest part of your bottom.
Measure each one twice and use the average. For tracking, measure at the same time of day, ideally first thing in the morning, so the numbers are comparable from week to week.
How accurate is it?
The formulas come from US Navy research by Hodgdon and Beckett (1984), who compared tape measurements with underwater weighing. Like every quick method (including bathroom scales that "measure" body fat), it is an estimate: expect it to be a few percentage points off, and further for very muscular or very lean people.
That matters less than it sounds. The real value is the trend: measured the same way every week or two, a falling waist and a falling estimate tell you the fat loss is working. That is also why the scale alone can mislead you.
What the ranges mean
The ranges follow the American Council on Exercise (ACE) chart. For men: essential fat is below 6%, athletic 6 to 13%, fit 14 to 17%, average 18 to 24%, and 25% or more is above average. For women, each range sits 7 to 8 points higher: essential fat is below 14%, athletic 14 to 20%, fit 21 to 24%, average 25 to 31%, and 32% or more is above average.
Stage-lean bodybuilders reach the essential range only briefly, for a show, and it is not a healthy place to stay. Read what the weeks before a show look like for why.
Next steps
Losing fat without losing muscle comes down to a moderate deficit, enough protein and hard training: see how to lose fat without losing muscle. Or apply for coaching and have your measurements, weight and photos reviewed with you every week.
General guidance for adults, not medical advice. It is not suitable during pregnancy.