Body Fat Calculator

Estimate your body fat percentage using the U.S. Navy circumference method. Enter your height, neck, waist, and hip (for women) measurements with just a tape measure—no scale required.

cm
cm
cm

Results

Enter your measurements and click Calculate

Formula (U.S. Navy Method)

Male

86.010 × log₁₀(waist − neck) − 70.041 × log₁₀(height) + 36.76

Female

163.205 × log₁₀(waist + hip − neck) − 97.684 × log₁₀(height) − 78.387

* All measurements should be entered in centimeters.

Body Fat Percentage Standards

CategoryMaleFemale
Essential Fat2–5%10–13%
Athlete6–13%14–20%
Fitness14–17%21–24%
Average18–24%25–31%
Obese25%+32%+

How to Use

  1. STEP 1
    Select your gender
  2. STEP 2
    Enter your height in cm
  3. STEP 3
    Measure and enter neck, waist (and hip for women) circumferences using a tape measure
  4. STEP 4
    Click 'Calculate' to see your estimated body fat percentage
  • Results are estimates using the U.S. Navy method and may differ from precise methods like DEXA or calipers
  • Stand relaxed and upright when taking circumference measurements
  • For the most consistent readings, measure in the morning before eating
  • Consult a healthcare professional for medical decisions

Body Fat Facts

1

BMI only uses height and weight, so muscular people can be classified as 'obese.' Body fat percentage is a more accurate indicator of body composition

2

Healthy body fat ranges are 10–20% for men and 20–30% for women

3

Two people at the same weight can look completely different depending on their muscle-to-fat ratio

4

Dropping below essential fat levels (2–5% male, 10–13% female) can impair hormonal balance and immune function

5

1 kg of fat equals about 7,700 kcal. To lose 1 kg per month, you need a daily deficit of about 250 kcal

FAQ

  • Q1

    How accurate is the U.S. Navy method?

    Studies show it has a ±3–4% margin of error compared to DEXA. While not perfect, it's one of the most reliable methods you can do at home with just a tape measure.

  • Q2

    Where exactly do I measure my waist?

    Measure around your navel, keeping the tape horizontal. Stand relaxed with normal breathing. The tape should fit snugly but not compress the skin.

  • Q3

    BMI vs Body Fat % — which matters more?

    Body fat percentage more accurately reflects your body composition. BMI doesn't account for muscle mass, so athletic people may be misclassified. Ideally, use both together.

  • Q4

    How can I lower my body fat percentage?

    A combination of caloric control and exercise (especially strength training) is most effective. Avoid rapid weight loss, which can cause muscle loss. Aim for a gradual 1–2% decrease per month.

  • Q5

    Where do I measure my neck?

    Measure just below the Adam's apple at the narrowest point. Keep the tape horizontal and allow one finger of slack.

This information is general guidance. Consult a doctor or specialist for health-related decisions.

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