How does the Body Fat Calculator work?
This calculator estimates body fat percentage using the U.S. Navy circumference method. It uses height, neck, waist, and for women, hip measurements.
Fitness Calculator
Body Fat Calculator
Estimate your body fat percentage using height, neck, waist, and hip measurements. Use the U.S. Navy circumference method to get a practical body composition estimate.
Your Measurement
Required for choosing the correct U.S. Navy formula.
Use the same unit for all measurements. The calculator converts centimeters to inches internally.
Height is entered in feet and inches like the other GameCalcPro measurement pages.
in
in
in
For female calculations, hip circumference is required. For male calculations, it is not used.
Optional. If entered, the calculator will show lean body mass and fat mass in the same unit.
Disclaimer: GameCalcPro calculators are provided for informational and educational purposes only. Results are estimates and should not be considered medical, fitness, nutrition, or professional advice. Always consult a qualified healthcare provider, trainer, or other appropriate professional before beginning or changing any exercise, diet, or training program, especially if you have a medical condition, injury, or health concern.
How Body Fat Works
What Is a Body Fat Calculator?
This calculator estimates body fat percentage using the U.S. Navy circumference method. It uses height, neck, waist, and for women, hip measurements.
How To Calculate Body Fat Percentage
Measure each body part carefully using the same unit. If you enter centimeters, the calculator converts them to inches before applying the Navy formula.
Body Fat Formula
For men: Body Fat % = 86.010 × log10(waist - neck) - 70.041 × log10(height) + 36.76
For women: Body Fat % = 163.205 × log10(waist + hip - neck) - 97.684 × log10(height) - 78.387
Use inches for all measurements. The calculator converts centimeters to inches automatically.
How To Take Body Measurements
Measure height, neck, waist, and hips carefully with a flexible tape measure. Keep the tape snug but not tight, and measure in a consistent position each time.
Body Fat vs BMI
Body fat percentage can give more detail about body composition than BMI because BMI only compares height and weight. Both are estimates, not perfect health measurements.
About The Calculation
The calculator uses the U.S. Navy circumference method with height, waist, neck, and hip measurements.
Centimeters are converted to inches before the formula is applied.
The final body fat estimate is rounded to 1 decimal place and shown as a percentage.
Body Fat Percentage Chart
Quick reference ranges
| Category | Men | Women |
|---|---|---|
| Essential Fat | 2%–5% | 10%–13% |
| Athletes | 6%–13% | 14%–20% |
| Fitness | 14%–17% | 21%–24% |
| Average | 18%–24% | 25%–31% |
| Obese | 25%+ | 32%+ |
Tips For Measuring Body Fat Safely
Measure Consistently
Take measurements the same way each time so your progress tracking stays useful.
Use A Flexible Tape
A flexible tape measure helps you get accurate circumference measurements.
Track Over Time
Body fat trends are more useful than a single measurement on one day.
Use Estimates Wisely
This calculator is a starting point, not a medical or laboratory measurement.
Frequently Asked Questions
Common questions about body fat
Is this body fat calculator exact?
No. This calculator gives an estimate. Measurement accuracy, hydration, body shape, and individual differences can affect the result.
What measurements do I need?
Men need height, neck, and waist measurements. Women need height, neck, waist, and hip measurements.
Can I use centimeters?
Yes. Enter your measurements in centimeters and the calculator will convert them to inches before applying the formula.
Is body fat percentage better than BMI?
Body fat percentage can give more detail about body composition than BMI because BMI only compares height and weight. However, both are estimates and should not be used as the only measure of health.
How often should I measure body fat?
For tracking progress, measuring every 2 to 4 weeks is usually more useful than measuring every day.