How accurate is the US Navy method?

It is usually accurate within 3–4% of DEXA scans when measurements are taken correctly. Consistency of tape placement matters more than absolute precision.

How do I measure my neck and waist?

Measure the neck just below the larynx, with the tape sloping slightly downward at the front. For waist, measure at the navel for men and at the narrowest point for women.

What is a healthy body fat percentage?

For men, 14–18% is generally considered fit. For women, 21–25%. Essential fat minimums are around 2–5% for men and 10–13% for women.

Does this calculator work for athletes?

It can under- or over-estimate for very muscular or very lean people. For athletes, a DEXA scan or hydrostatic weighing gives more precise results.

Why do women have higher healthy body fat than men?

Women naturally carry more essential fat for reproductive and hormonal health — around 10–13% minimum vs 2–5% for men. Below these thresholds, hormonal and menstrual dysfunction becomes likely.

What is the most accurate way to measure body fat?

DEXA (dual-energy X-ray absorptiometry) is the clinical gold standard, accurate within 1–2%. Hydrostatic weighing and the Bod Pod are close behind. Consumer scales and handheld devices are less accurate — often ±5–8%.

Body Fat Calculator

Estimate your body fat percentage using the US Navy method — a tape-measure formula trusted by the military and fitness professionals. Enter a few circumference measurements and see your body fat percentage, fat mass and lean mass.

How to use

Enter your gender, height and weight

Type your biological sex, height and weight.

Measure your neck

Measure the circumference of your neck just below the larynx.

Measure your waist

Measure at the navel for men, or at the narrowest point for women.

Measure your hips (women only)

Women also need to measure hip circumference at the widest point.

Read your body fat percentage

See your body fat percentage, fat mass and lean mass.

Features

US Navy method

Uses the standard circumference-based formula trusted by the military and fitness professionals.

Fat mass and lean mass

See how many kilograms of your weight are fat and how many are lean tissue.

Category ranges

See where your body fat percentage falls: essential, athletic, fitness, average or obese.

Metric and imperial

Enter measurements in centimeters or inches.

Common use cases

Track body composition changes during a fitness program
Estimate body fat without expensive equipment
Set realistic body composition goals
Monitor lean mass during a cut or bulk

Frequently Asked Questions

Related tools

BMI Calculator

Ideal Weight Calculator

Calorie Calculator

TDEE & Macro Calculator