How to Calculate Body Fat
What is Body Fat?
Body fat percentage is the proportion of your total body mass that is fat tissue. Unlike BMI, body fat percentage distinguishes between fat and lean mass (muscle, bone, water), making it a more accurate indicator of fitness and health risk.
Step-by-Step Guide
- 1Measure height, neck circumference, and waist circumference in inches
- 2For women, also measure hip circumference
- 3Apply the US Navy formula: Men: 86.010×log(waist−neck) − 70.041×log(height) + 36.76
- 4Women: 163.205×log(waist+hip−neck) − 97.684×log(height) − 78.387
- 5Compare result to age and sex-specific body fat categories
Worked Examples
Input
Male, height 175cm, neck 38cm, waist 85cm
Result
~18% body fat
Fitness category
Input
Female, height 165cm, neck 33cm, waist 75cm, hip 97cm
Result
~26% body fat
Average/acceptable category
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