BMI calculator
Calculate BMI (body mass index) using the WHO formula. Check whether you are underweight, normal, overweight or obese. Free BMI calculator.
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Calculator · Health
Body fat percentage calculator
Calculate your body fat percentage using the US Navy method (neck, waist and hip circumferences) or based on BMI. Find out whether your body composition is healthy.
How we calculate body fat
Navy method: a formula based on body circumferences and height. BMI-based: a simplified estimate derived from the body mass index.
Example: man, waist 90 cm, neck 38 cm, height 180 cm
By the Navy method: %BF ≈ 18.5% (healthy range for men: 14–24%).
Frequently asked questions
How does the US Navy method work?
It estimates body fat from the circumference of the neck, waist and (for women) hips, combined with height. It needs only a tape measure.
What is a healthy body fat percentage?
For men a typical healthy range is about 14–24% and for women about 21–31%. Athletes usually fall below these ranges.
Is the BMI-based estimate accurate?
It is only a rough approximation. BMI does not distinguish muscle from fat, so the Navy method is generally more reliable.
How should I measure the circumferences?
Measure the neck below the larynx, the waist at the narrowest point (men at the navel), and hips at the widest point, keeping the tape level.
How often should I re-measure?
Every two to four weeks is enough to track a trend. Measure at the same time of day under the same conditions for consistency.
Which method is most accurate overall?
Laboratory methods such as DEXA scans or hydrostatic weighing are the most accurate. Tape-based formulas only estimate the value.
Indicative result
The result is for guidance only. For an accurate measurement use DEXA, hydrostatic weighing or caliper testing.
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