Lunia · Free tools
Body Fat Calculator
Estimate body fat from height and tape measurements using a circumference model.
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Enter your details, then calculate to see your result here.
How this calculator works
This uses the U.S. military circumference equations, with measurements converted to inches. The male equation uses waist minus neck; the female equation uses waist plus hip minus neck. Height and logarithmic circumference terms produce the percentage.
A worked example
Height: 170 · Length unit: Centimetres · Sex coefficient used by the formula: Female coefficient · Waist circumference (same length unit): 78 · Neck circumference (same length unit): 34 · Hip circumference (female equation): 96
- Estimated body fat
- 27.5%
These are illustrative inputs, not personal recommendations.
Common questions
Should I pull the measuring tape tight?
Keep it level and snug without compressing the skin. Repeat each measurement consistently rather than choosing the smallest number.
How should I use the result?
Tape placement changes the result substantially. Use a relaxed abdomen at the navel for the male equation, the narrowest natural waist and fullest hip for the female equation, and the neck just below the larynx. This is not a clinical body-composition measurement.
Sources & method references
Formula-based results are estimates, not individual medical advice.