Body Fat Calculator
Estimate body fat percentage with the US Navy tape method and see your fat and lean mass in kg.
Inputs
Formula
- Men: 495 / (1.0324 − 0.19077·log10(waist − neck) + 0.15456·log10(height)) − 450
- Women: 495 / (1.29579 − 0.35004·log10(waist + hip − neck) + 0.22100·log10(height)) − 450
The US Navy method uses tape measurements instead of calipers, so it is easy to repeat at home. Measure at the same time of day, relaxed, with the tape snug but not tight. Trends matter far more than any single reading.
Step-by-step calculation
- 1
Navy formula
log-based circumference model
17.4%
Frequently asked questions
What does the Body Fat Calculator do?
Estimate body fat percentage with the US Navy tape method and see your fat and lean mass in kg. The Body Fat Calculator on OneCalcApp returns the result instantly as you type, together with the formula and the substituted values.
How do I use the Body Fat Calculator?
Enter your values in the input fields, choose the relevant units or options, and the Body Fat Calculator recalculates automatically. You can copy, print or export the result.
Is the Body Fat Calculator free to use?
Yes. The Body Fat Calculator is completely free, needs no sign-up and has no usage limit on OneCalcApp.
How accurate is the Body Fat Calculator?
It uses the standard formula Men: 495 / (1.0324 − 0.19077·log10(waist − neck) + 0.15456·log10(height)) − 450 and full double-precision arithmetic, so results match a manual calculation to the displayed number of digits.
Does the Body Fat Calculator work on mobile and offline?
Yes. The Body Fat Calculator runs entirely in your browser on phones, tablets and desktops, and your inputs never leave your device.
Where can I find related tools?
OneCalcApp hosts 300+ calculators and converters, including the full Health collection. Related tools are linked at the bottom of every page.
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