What is the Navy Method for body fat?

The US Navy circumference method estimates body fat percentage using height, neck, waist, and (for women) hip measurements. It was developed by the US Navy for fitness assessments and is widely used due to its simplicity and reasonable accuracy.

How accurate is this body fat calculator?

The Navy method has a margin of error of roughly ±3–4% compared to DEXA scan (the gold standard). It is most accurate for people in the average-to-fitness range. Very muscular or obese individuals may see larger errors.

Where do I measure my waist?

For men, measure the waist at the navel. For women, measure at the narrowest point of the torso (usually just above the navel). Stand relaxed — do not suck in.

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Body Fat Calculator

Estimate your body fat percentage using the US Navy circumference method — the most practical tape-measure approach. Get your category, fat mass, and lean mass instantly.

Biological sex

Units

Height (cm)

Neck circumference (cm) Measure just below the larynx

Waist circumference (cm) Measure at navel (men) or narrowest point (women)

Weight (kg) Optional — used to calculate fat mass & lean mass

Age Optional — used for BMI-based comparison

Understand your body fat percentage

Body weight alone doesn't tell the whole story — two people with the same weight can have very different body compositions. Body fat percentage measures the proportion of your body that is fat versus lean tissue (muscle, bone, water, organs).

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Navy method

The US Navy circumference method uses simple tape measurements to estimate body fat. It's widely used in fitness and military settings because it requires no equipment beyond a tape measure.

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Know your category

Essential fat keeps the body alive. Athletic and fitness ranges indicate a lean, active physique. Average is healthy for most adults. The obese range correlates with increased health risk.

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Fat mass vs lean mass

Knowing how much of your body weight is fat vs lean tissue helps set realistic goals. Strength training can increase lean mass while reducing fat mass even when scale weight doesn't change much.

Body fat percentage is a useful companion to the TDEE calculator for setting calorie goals and the BMI calculator for a broader health picture. For a full fitness toolkit, also try the health calculators.

Frequently Asked Questions

What is the US Navy body fat method?

It uses circumference measurements (height, neck, waist, and hips for women) to estimate body fat percentage. The formula was developed by the US Department of Defense and is widely used for fitness assessments because it's quick and requires only a tape measure.

How accurate is this calculator?

The Navy method typically has a margin of error of ±3–4 percentage points compared to DEXA scan (the gold standard). It's most accurate for people in the average or fitness range. Very muscular athletes may get slightly high readings; very obese individuals may get lower readings.

Where exactly should I measure?

Neck: just below the larynx (Adam's apple), tilting slightly forward. Waist (men): at the navel. Waist (women): at the narrowest point, usually just above the navel. Hips (women): at the widest point around the buttocks. All measurements at a relaxed, normal exhale — don't suck in.

What is a healthy body fat percentage?

Men: 6–17% is athletic to fitness range; 18–24% is average/acceptable. Women: 14–24% is athletic to fitness; 25–31% is average/acceptable. These are general guidelines — individual health varies. Consult a healthcare professional for personalized advice.

Why does my result differ from other calculators?

Small differences come from rounding measurements or using slightly different constants in the formula. The Navy method formula is standardized but different sites may use the inches vs cm version. This calculator converts all inputs to inches before applying the DODNA formula.