How this Body Fat Calculator Works
This calculator relies on the U.S. Navy Method, a widely accepted formula for estimating body fat percentage based on specific body measurements. It compares the circumference of certain body parts against your height to determine body composition.
The U.S. Navy Method Formula
Note: The formulas use log base 10. Measurements are in centimeters for the standard calculation.
Men: 86.010 × log10(waist - neck) - 70.041 × log10(height) + 36.76
Women: 163.205 × log10(waist + hip - neck) - 97.684 × log10(height) - 78.387
Body Fat Categories
Based on the American Council on Exercise (ACE) guidelines:
| Category | Women | Men |
|---|---|---|
| Essential Fat | 10-13% | 2-5% |
| Athletes | 14-20% | 6-13% |
| Fitness | 21-24% | 14-17% |
| Average | 25-31% | 18-24% |
| Obese | 32%+ | 25%+ |
How to Measure Correctly
- Neck: Measure below the larynx (Adam's apple) sloping slightly downward to the front.
- Waist (Men): Measure at the navel level.
- Waist (Women): Measure at the narrowest point of the waist.
- Hips (Women only): Measure at the widest point of the hips.
Step-by-Step Instructions
- Select Units: Choose between Metric (cm) or Imperial (inches).
- Select Gender: This determines which formula is used (women require hip measurement).
- Input Measurements: Enter your height, neck, waist, and hip (if applicable) measurements carefully.
- Check Result: The calculator will display your estimated percentage and categorize your fitness level.