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Body fat and lean mass

A tape measure and two equations. It is three or four points out on an individual, so it is worth having for the trend rather than for the number.

Your measurements

The US Navy formula has a separate version for each, and the female one also uses your hips.

Without shoes.

Used to turn the percentage into kilograms of fat and lean mass, not to find the percentage itself.

Just below the larynx, tape sloping slightly down at the front. Pull it snug, not tight.

cm

At the navel, breathing out normally rather than holding it in.

cm
5 still to fill in

Tape measure estimate

Fill in the boxes and press Calculate. Nothing is worked out until you ask for it.

  • Which equation
  • Height
  • Bodyweight
  • Neck
  • Waist

Nothing is sent anywhere. The sum happens in this tab, and the measurements are only saved if you ask.

How wrong each way of measuring body fat typically is typical error, in percentage points of body fat DEXA scan 2 to 3 hydrostatic 2 to 3 skinfold calipers 3 to 5 tape measurements 4 to 6 visual comparison about 5 impedance scale 5 to 10 0 5 10 The trend from one consistent method beats one accurate reading.
The bar is the error, not the reading. The cheapest method is wrong by more than the gap people worry about.
Read how this is worked out