Body Fat Calculator
Calculate your body fat percentage and composition using the US Navy method with circumference measurements.
Neck circumference (below larynx) and Waist circumference (at navel)
Body Composition
📊 Body Composition Breakdown
📈 Body Fat Categories
💡 Body Fat Tips
- • Measure consistently at the same time of day (preferably morning)
- • Use a flexible tape measure, not rigid rulers
- • This uses the US Navy method, other methods may vary
- • Body fat percentage is better indicator of fitness than weight
- • Focus on muscle building and fat loss, not just weight loss
- • Essential body fat for males: 2-5%, females: 10-13%
Formula
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
US Navy Method - Measurements in centimeters
How it works
Male Formula: Body Fat % = 86.010 × log₁₀(waist - neck) − 70.041 × log₁₀(height) + 36.76 Female Formula: Body Fat % = 163.205 × log₁₀(waist + hip - neck) − 97.684 × log₁₀(height) − 78.387 Where: All measurements in centimeters US Navy Method (NCAB - Navy Circumference Assessment) Example: Male: Neck 38cm, Waist 85cm, Height 175cm = ~18% body fat Female: Neck 32cm, Waist 70cm, Hip 95cm, Height 165cm = ~26% body fat
The body fat calculator uses the US Navy method to estimate your body composition based on circumference measurements. Enter your measurements (neck, waist, and hip for women) along with your height to calculate body fat percentage, fat mass, and lean body mass. Includes body composition categories and comparison to fitness standards.
Why this matters
Body fat percentage is a more accurate measure of fitness and health than weight alone. Understanding your body composition helps you track progress in fitness programs and make informed health decisions. The US Navy method is quick, non-invasive, and doesn't require special equipment.
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The complete guide to body fat calculator
Formulas, examples, and tips explained in plain English