Body fat calculator

It is a reasonable estimate, not a precise measurement, so expect a few percentage points either way. The method uses tape measurements of your neck, waist and height (plus hips for women), which is why it needs no scales or scan. Use it to track change over time rather than as an exact figure. This is general information, not a medical measurement.

They answer different questions. BMI is a quick screen from height and weight that works well across a population but cannot tell muscle from fat for one person. Body fat percentage measures composition directly, so it shows how much of your weight is actually fat, but it is harder to measure accurately at home. Used together they cover each other blind spots.

If you are muscular, very lean, or tracking a body recomposition, body fat percentage gives a fairer read because it shows whether you are losing fat while holding muscle, which the scale alone hides. The catch is accuracy: home methods such as tape measurements or bioelectrical scales give estimates that can vary.

A DEXA scan is generally treated as the gold standard, as it maps fat, muscle and bone directly, though it needs a clinic and a fee. Home methods such as this tape-measure estimate or a bioelectrical scale are far more convenient and are good enough for tracking change. This is general information, not a medical assessment.