Estimate your body fat percentage using the US Navy method. Free body composition tool.
Estimate body fat using the US Navy method
This free calculator gives you instant, accurate results with no signup required. Use it to make smarter, more informed financial and life decisions.
Always double-check important financial decisions with a qualified professional. This calculator provides estimates for guidance purposes. Results may vary based on your specific circumstances.
Body fat percentage gives a far more accurate health picture than weight or BMI alone, since it distinguishes between fat mass and lean mass — two people at identical weight and height can have wildly different body compositions and health profiles.
Healthy ranges differ significantly by sex due to biological differences in essential fat storage. For men, 10-20% is generally considered fit/healthy, while women's healthy range runs higher at 18-28%, reflecting natural hormonal and reproductive biology.
The U.S. Navy method used in this calculator (based on neck and waist measurements) isn't as precise as DEXA scans or hydrostatic weighing, but it's far more accessible and still reasonably accurate for tracking trends over time — which matters more than any single precise number.
Use the calculator above and re-measure every 4-6 weeks rather than daily — body fat percentage changes slowly, and frequent measuring just introduces noise from water retention and measurement inconsistency rather than real signal.