How it works
The US Navy method estimates body fat percentage from neck, waist, and height measurements (plus hips for women).
Uses logarithmic formulas based on circumference measurements.
How to take the measurements
Measure the neck just below the larynx, the waist at the navel, and (for women) the hips at the widest point. Keep the tape snug but not tight, and measure against bare skin for accuracy.
How accurate is it?
The US Navy method is a reasonable estimate but is less precise than methods like DEXA or hydrostatic weighing. Consistency in how you measure matters most for tracking changes over time.