Power Calculators

⚖️ Body Fat Percentage Calculator

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📏 How to measure for body fat (US Navy method)Tap to see the illustrated guide
Illustration: how to measure for body fat (us navy method) — Neck: just below the Adam's apple, tape sloping slightly down to the front. Waist: men at the belly button; women at the narrowest point of the waist. Breathe out, don't pull in.
  1. Neck: just below the Adam's apple, tape sloping slightly down to the front.
  2. Waist: men at the belly button; women at the narrowest point of the waist. Breathe out, don't pull in.
  3. Hips (women only): round the widest part of the buttocks.
  4. Measure height barefoot. Take each measurement twice and use the average.
Men: at the belly button. Women: at the narrowest point. Breathe out.
Just below the Adam's apple, tape sloping slightly down at the front.
Women only: widest part of the buttocks.

Fill in the details and click Calculate to see your results.

Formula at a glance

Body Fat % formula: Body fat % = 495 ÷ [1.0324 − 0.19077 × log₁₀(waist − neck) + 0.15456 × log₁₀(height)] − 450; Body fat % = 495 ÷ [1.29579 − 0.35004 × log₁₀(waist + hip − neck) + 0.22100 × log₁₀(height)] − 450
How the body fat % works: Body fat % = 495 ÷ [1.0324 − 0.19077 × log₁₀(waist − neck) + 0.15456 × log₁₀(height)] − 450

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📘 About the Body Fat %

Body fat percentage tells you how much of your weight is fat. This calculator uses the US Navy circumference method, which needs only a tape measure and gives a practical estimate without special equipment.

Enter your gender, height, neck and waist measurements, and hip too if you are female, all in centimetres.

🧮 Formula

Men
Body fat % = 495 ÷ [1.0324 − 0.19077 × log₁₀(waist − neck) + 0.15456 × log₁₀(height)] − 450
Women
Body fat % = 495 ÷ [1.29579 − 0.35004 × log₁₀(waist + hip − neck) + 0.22100 × log₁₀(height)] − 450

Where

  • All measurements in centimetres
  • Measure the neck just below the larynx and the waist at the navel (men) or narrowest point (women); hips at the widest point

✏️ Worked examples

Man: 175 cm, waist 90 cm, neck 38 cm, 80 kg

You enter
GenderMale
Waist90 cm
Neck38 cm
Hip (women only)0 cm
Height175 cm
Weight (optional, for fat mass)80 kg
You get
Body fat percentage20.7%
Category (ACE)Average
Fat mass16.5 kg
Lean body mass63.5 kg
Healthy "fitness" range for men14 – 17%

Body fat 20.7% — Average. Fat mass 16.5 kg.

Try this example →

Woman: 162 cm, waist 76 cm, neck 33 cm, hip 98 cm

You enter
GenderFemale
Waist76 cm
Neck33 cm
Hip (women only)98 cm
Height162 cm
You get
Body fat percentage29.8%
Category (ACE)Average
Healthy "fitness" range for women21 – 24%

Body fat 29.8% — Average.

Try this example →

🧭 How to use this calculator

What you enter

  • Gender
  • Waist (cm)Men: at the belly button. Women: at the narrowest point. Breathe out.
  • Neck (cm)Just below the Adam's apple, tape sloping slightly down at the front.
  • Hip (women only) (cm)Women only: widest part of the buttocks.
  • Height (cm)
  • Weight (optional, for fat mass) (kg)

What you get

  • Estimated Body Fat
  • Fat Mass (kg)
  • Lean Body Mass (kg)

💡 Body fat percentage chart (ACE)

  • Essential fat: men 2–5%, women 10–13%
  • Athletes: men 6–13%, women 14–20%
  • Fitness: men 14–17%, women 21–24%
  • Average: men 18–24%, women 25–31%
  • Obese: men 25%+, women 32%+

💡 How to measure

  • Neck: just below the Adam's apple, tape sloping slightly down at the front.
  • Waist: men at the navel; women at the narrowest point.
  • Hips (women): widest part of the buttocks.
  • Measure in centimetres, take each reading twice and use the average.

❓ Frequently asked questions

How accurate is the Navy method?

It is an estimate, typically within a few percentage points. DEXA scans and skinfold tests are more precise.

Why is hip needed only for women?

The formula for women uses hip circumference because fat is stored differently.

How often should I measure?

Once every few weeks, at the same time of day, to see a trend rather than a single reading.

What is a healthy body fat percentage?

Roughly 14–24% for men and 21–31% for women covers the fitness and average ranges on the ACE chart.

How do I calculate body fat percentage at home?

Use a tape measure for neck, waist (and hips for women) and enter them with your height. This Navy formula is within about 3–4% of lab tests for most people.

What is lean body mass?

Everything that is not fat — muscle, bone, organs and water. Add your weight to see it.

What people are saying
★★★★★
Anonymous · 29 Sep 2026