What is Body Fat Calculator?
The US Navy circumference method is a scientifically validated technique using tape measurements of the neck, waist, and hips to estimate subcutaneous and visceral adipose tissue with a 3-4% margin of error compared to DEXA scans.
How to Use This Calculator
- Measure your neck circumference horizontally below the larynx.
- Measure waist circumference horizontally around the navel.
- Females must also measure the widest circumference of the hips.
- Review your total fat mass and lean mass breakdown.
The Mathematical Formula & Variables
Men: 86.010 * log10(waist - neck) - 70.041 * log10(height) + 36.76; Women incorporates hip circumference.
Variables Definition
| Symbol / Variable | Name | Description |
|---|---|---|
Tape Accuracy |
Circumference in Inches | Must be pulled snug against skin without compressing soft tissue. |
Step-by-Step Worked Example
Scenario: Male, Height 70 in, Neck 15.5 in, Waist 33 in, Weight 170 lbs.
- Waist minus neck = 33 - 15.5 = 17.5 in.
- Log10(17.5) = 1.2430; Log10(70) = 1.8451.
- BF% = (86.010 * 1.2430) - (70.041 * 1.8451) + 36.76 = 106.91 - 129.23 + 36.76 = 14.44%.
- Fat mass = 170 * 0.1444 = 24.5 lbs. Lean mass = 145.5 lbs.
Result: Body Fat = 14.4% (Fitness Range)
Frequently Asked Questions
What is a healthy body fat percentage?
For men, 10-20% is considered healthy (under 14% is athletic). For women, 18-28% is healthy (under 21% is athletic).