Body Fat Calculator
The US Navy method estimates your body fat percentage with just a tape measure, no calipers needed. Enter your waist, neck, height (and, for women, hip circumference) for an indication.
Result
16.4%
Estimated body fat
Formula
Male: 495 รท (1.0324 โ 0.19077รlog(waistโneck) + 0.15456รlog(height)) โ 450
This formula, developed for the US Navy, uses logarithmic ratios between waist circumference (minus neck) and height to estimate body fat without special equipment. For women, hip circumference is also included, since fat distribution differs.
Worked examples
Male: waist 90 cm, neck 38 cm, height 180 cm
โ Estimated body fat โ 19.8%.
Common mistakes
- Measuring waist circumference above the navel instead of at the narrowest point, skewing the estimate.
Important to know
- This is an estimate, not a medical measurement. Consult a doctor for an accurate assessment.
Limitations
- This method is less accurate than a DEXA scan or hydrostatic weighing, but useful for tracking trends.
When to use it
- Tracking your body composition as a complement to weight alone.
Frequently asked questions
How accurate is the US Navy method?
Studies show a margin of error of a few percentage points; it is suitable for tracking trends, not exact diagnosis.
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