Body Fat Calculator
Body fat % = 495 ÷ Body density − 450 (US Navy method)Body density ≈ 1.057, then 495/1.057 − 450 ≈ 18.3%
Free online tool
Body Fat Calculator
Enter your measurements to estimate your body fat percentage and lean body mass.
Instant calculation
Calculate Body Fat Percentage
Enter your measurements.
Your result
Calculation
Your numbers stay in this browser. Nothing is uploaded or saved.
Three clear steps
How to use this calculator
- 01
Select gender
Choose male or female for the appropriate formula.
- 02
Enter measurements
Type your height, neck and waist (and hip if female) measurements.
- 03
See results
Calculate to see body fat percentage, fat mass and lean body mass.
The formula
How this calculation works
Uses circumference measurements to estimate body density, then converts to body fat percentage. Different equations for males and females.
Check the method
Worked examples
Each example follows the same formula used by the calculator.
Male, 170 cm, neck 38 cm, waist 85 cm — body fat?
Body density ≈ 1.057, then 495/1.057 − 450 ≈ 18.3%≈ 18.3% body fatCommon questions
Questions about this calculation
What is the Body Fat Calculator?
The Body Fat Calculator helps you estimate your body fat percentage using the US Navy method. Enter your values and select Calculate to get an instant result.
How is the result calculated?
Uses circumference measurements to estimate body density, then converts to body fat percentage. Different equations for males and females.
Can you show an example?
Example: Male, 170 cm, neck 38 cm, waist 85 cm — body fat? — ≈ 18.3% body fat.
Is my data saved when I use the Body Fat Calculator?
No. All calculations run locally in your browser. Your inputs and results are never uploaded, stored or shared with anyone.
Is the Body Fat Calculator free to use?
Yes. The Body Fat Calculator is completely free. No account, sign-up or payment is required. It works on mobile, tablet and desktop.
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