Health & Fitness calculator
Body Fat % Calculator
Estimate body fat percentage using the US Navy method.
About the body fat % calculator
The body fat percentage calculator estimates body fat using the US Navy method, which uses circumference measurements.
How to use this calculator
- 1
Enter body details
Enter weight, height, waist, neck, and gender.
- 2
View results
See your estimated body fat percentage and category.
How the calculation works
Male: 495 ÷ (1.032 − 0.191 × log10(waist−neck) + 0.154 × log10(height)) − 450. Female uses hip measurement.
Example: 80 kg, 180 cm, 90 cm waist, 38 cm neck male: ≈ 20%.
Important health disclaimers
These calculators provide estimates based on population averages. Individual results vary based on genetics, body composition, medical conditions, and medications. Always consult a healthcare provider before starting a new diet or exercise program, especially if you have underlying health conditions.
Understanding body composition metrics
BMI doesn't distinguish muscle from fat. Body fat % is more accurate but depends on measurement technique. TDEE varies day-to-day based on activity. Macro targets are starting points — adjust based on your results, energy levels, and goals. Hydration needs increase with exercise, heat, and altitude.
Important limitations
This tool provides a mathematical estimate based only on the values entered. It does not account for regulations, taxes, lender fees, market conditions, or individual circumstances. Results are for planning purposes only — consult a qualified professional for regulated, medical, financial, or construction decisions.
Frequently asked questions about body fat % calculator
How accurate is the body fat calculator?+
The calculation follows the displayed formula and retains full numeric precision before formatting the result.
Can I use the result professionally?+
Use it as a planning estimate. Confirm regulated, medical, financial, or construction decisions with a qualified professional.