Male formula
86.010×log10(waist-neck) - 70.041×log10(height) + 36.76
Body Fat Calculator (Navy Method)
Navy Method
Measure neck, waist, and hip circumferences for an accurate body fat estimate.
Body Fat %
21.8%
Acceptable
Fat Mass
15.3 kg
Lean Mass
54.7 kg
Ideal Weight Range
56.7 — 76.3 kg
The Navy method estimates body fat from circumference measurements
This calculator uses height, weight, neck, waist, and for women hip circumference to estimate body fat percentage with the U.S. Navy method. It also converts the percentage into fat mass, lean mass, and an ideal-weight range based on BMI, giving more context than scale weight alone.
Core concepts
Female formula
163.205×log10(waist+hip-neck) - 97.684×log10(height) - 78.387
Body composition
Fat mass = weight×body-fat %, lean mass = weight-fat mass
How to use
- Select sex and enter height, weight, neck, and waist measurements.
- If female is selected, enter hip circumference as well.
- Review body fat, fat mass, and lean mass while keeping measurement placement consistent.
Frequently asked questions
Is the Navy method accurate?
It can be a useful estimate when measurements are consistent, but it is not a direct body-composition test such as DEXA.
Why does the formula use neck circumference?
The Navy method compares neck and waist, and hip for women, to estimate body-fat distribution from body shape.
Can results change during the day?
Yes. Meals, hydration, exercise, posture, and tape tension can affect circumference measurements.
Results are general estimates and are not a substitute for professional medical advice, diagnosis, or treatment.