Body Fat Calculator

Estimate your body fat percentage using the US Navy method

Measurements

Gender

Male Female

Height (cm)

Neck circumference (cm)

Waist circumference (cm) — at navel

Hip circumference (cm) — widest point

Weight (kg) — optional, for lean mass calc

Results

Body Fat Percentage

—

Ess.

Athlete

Fit

Avg

Obese

▲

—

Body Fat Mass—

Lean Body Mass—

About the US Navy Body Fat Method

The US Navy body fat formula uses circumference measurements to estimate body fat percentage. It was developed by Hodgdon and Beckett at the Naval Health Research Center and is used by the US military for fitness assessments.

Formula

Men: %BF = 86.010 × log10(waist - neck) - 70.041 × log10(height) + 36.76

Women: %BF = 163.205 × log10(waist + hip - neck) - 97.684 × log10(height) - 78.387

Body Fat Categories (Men / Women)

Essential Fat: 2-5% / 10-13%
Athletes: 6-13% / 14-20%
Fitness: 14-17% / 21-24%
Average: 18-24% / 25-31%
Obese: 25%+ / 32%+

Frequently Asked Questions

What is a healthy body fat percentage?

For men, essential fat is 2-5%, athletes 6-13%, fit 14-17%, average 18-24%, obese 25%+. For women, essential fat is 10-13%, athletes 14-20%, fit 21-24%, average 25-31%, obese 32%+.

How accurate is the US Navy body fat method?

The US Navy method is accurate within 1-3% of DEXA scan results for most people. It uses circumference measurements and height to estimate body fat percentage.

How do I measure my waist correctly?

Measure at the narrowest point of your waist, typically at the navel level. Stand relaxed, don't suck in your stomach, and measure after exhaling normally.

Go deeper

Read the SnoopTool guide behind this tool

The calculator gives you the number. These SnoopTool guides explain the method, the assumptions and the decision — with worked examples, data tables and FAQs.

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