Enter your measurements
Keep the unit system consistent for every field. US Navy requires neck and waist (plus hip for women). BMI (Deurenberg) requires weight.
Results
Enter your measurements and choose a method to estimate body fat percentage.
Please check the highlighted fields and try again.
Body fat percentage
Category
Fat mass
Lean mass
For information only; measurement methods and individual factors vary. Not a medical diagnosis.
Measurement guide
- Neck: tape just below the Adam’s apple while looking forward.
- Waist: tape at the narrowest natural waist or navel line, after a gentle exhale.
- Hip (women): tape at the widest point over the buttocks.
- Consistency: take measurements at the same time of day, in minimal clothing, and average multiple readings.
US Navy and BMI formulas estimate population averages. Muscle mass, body shape, hydration, and ethnicity can shift results.
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FAQ
Which formulas does the body fat calculator use?
Choose the US Navy circumference method or the BMI-based Deurenberg equation. Both accept metric or US customary measurements and clip results to 0–75 %.
Is this body fat estimate medical advice?
No. These methods provide estimates only. Discuss health or training decisions with a clinician, registered dietitian, or certified coach.