Body Fat Calculator – Estimate Your Body Fat Percentage
Calculate your body fat percentage using the US Navy method. Get your fat mass, lean mass, and see which category you fall into based on your measurements.
Coach tip: Body fat percentage is more useful than BMI for athletic clients. However, for the most accurate measurements, consider DEXA scans or professional caliper testing. The US Navy method is a reliable estimation for tracking progress over time.
Enter Your Measurements
US Navy Method requires specific circumference measurements
Measure below the larynx (Adam's apple)
At navel level, horizontally
Your Results
Body composition breakdown
Enter your measurements to calculate body fat
Results will show your % and body composition
What is a Body Fat Calculator and Why Does Body Composition Matter?
A body fat calculator estimates the proportion of your total body weight that is composed of fat tissue, expressed as a percentage. Unlike bodyweight or BMI, body fat percentage distinguishes between fat mass and lean mass — giving you a far more meaningful picture of your actual body composition and health status.
This tool is valuable for fitness enthusiasts tracking progress beyond the scale, personal trainers assessing client body composition, athletes monitoring their conditioning, and anyone who wants a clearer understanding of their physical health. The scale alone cannot tell you whether you are losing fat, gaining muscle, or both simultaneously — body fat percentage can.
This calculator uses the US Navy Method, which estimates body fat from simple circumference measurements (neck, waist, and hips for women). This approach is accurate within 3–4% of gold-standard methods like DEXA scanning for most individuals and requires no specialist equipment. Understanding your body fat range — whether Athletic, Fitness, or Average — provides context that weight alone never can.
Knowing your healthy body fat range empowers better decision-making. Rather than chasing a number on the scale, you can set goals around body composition: reducing fat mass while preserving or building lean muscle. This is particularly important for those who exercise regularly, as muscle gain can mask fat loss when only tracking weight.
How to Use This Body Fat Calculator
- Select your gender and unit system (metric cm or imperial inches).
- Enter your height, and measure your neck and waist circumferences accurately with a flexible tape measure.
- Women also need to enter their hip circumference at the widest point.
- Optionally enter your weight to see your lean mass and fat mass in kilograms or pounds.
- Click "Calculate Body Fat %" to see your estimated body fat percentage, category, and recommended range.
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What is Body Fat Percentage?
Body fat percentage is the proportion of your total body weight that is fat tissue. Unlike BMI, it distinguishes between fat mass and lean mass (muscle, bone, organs, water), giving a more accurate picture of body composition.
The US Navy Method Formula:
Why Body Fat % Matters:
How to Measure Correctly
Accurate measurements = accurate results
Neck Measurement
Measure below the larynx (Adam's apple). Keep tape slightly downward at the front. Don't pull too tight.
Waist Measurement
Men: At navel level, horizontally
Women: At narrowest point (usually just above navel)
Hip Measurement (Women Only)
Measure at the widest point of the buttocks. Keep tape level all the way around.
Download Your Body Fat Report
Get a professional PDF summary with your body fat %, category, lean/fat mass breakdown, and personalized recommendations. Perfect for tracking progress or sharing with your coach.
Frequently Asked Questions
Common questions about body fat percentage
What to Do After Calculating Body Fat
Use these tools to create your complete fitness plan