Health
Body Fat Calculator
Estimate body fat percentage using the US Navy circumference method and break it down into lean versus fat mass.
US Navy method using circumference measurements for a solid quick estimate.
US Navy body fat equations
For males: %BF = 495 / [1.0324 − 0.19077 log₁₀(waist − neck) + 0.15456 log₁₀(height)] − 450. For females, replace the numerator with waist + hip − neck and swap constants per the Navy formula.
How to use
- Select gender to toggle the correct circumference fields.
- Enter height plus waist, neck, and (for females) hip measurements in centimeters.
- Provide body weight to translate the percentage into lean and fat mass estimates.
Example
Input: Male, Height = 175 cm, Waist = 85 cm, Neck = 38 cm, Weight = 75 kg
Output: Body fat ≈ 16.9%, Lean mass ≈ 62.4 kg, Fat mass ≈ 12.6 kg
FAQ & notes
How accurate is the US Navy method?
It provides a solid estimate when measurements are precise, but DEXA scans and calipers deliver more accurate body composition data.
Can I enter measurements in inches?
At the moment the calculator expects centimeters. Convert inches to centimeters (multiply by 2.54) before entering your numbers.