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Body measurements · Composition

Body Fat Calculator

Estimate body-fat percentage using widely used formula-based methods.

Your details

Sex
Height

Use a soft tape, standing relaxed. Measure 3× and average.

Your body fat
17.0%
< 10 %≥ 28 %
Athletes

Lean and performance-oriented.

Why body fat % matters

Body fat % gives a far richer picture than weight or BMI alone — distinguishing fat mass from lean tissue. It helps athletes calibrate cutting phases and ordinary adults understand cardiometabolic risk beyond the scale.

The US Navy method, explained

Developed for the US military, this method uses simple tape measurements. Remarkably accurate (±3% of DEXA) when measurements are precise. Men use waist − neck; women add hip circumference to account for essential fat distribution.

Measure well

Use a soft tape, stand relaxed, do not pull in. Measure first thing in the morning. Take three measurements at each site and average them.

Limitations & caveats

  • Estimates only — DEXA/BodPod are more precise.
  • 1 cm waist error ≈ 1.5% body fat shift.
  • Not designed for pregnancy or extreme muscularity.
  • Use the same method consistently when tracking.
  • BIA scales vary widely with hydration.
FAQ

Frequently asked questions

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Clinical Interpretation

AthletesNormal

Lean and performance-oriented.

Lifestyle considerations
  • •Sustainable for competitive athletes
  • •Sleep and recovery become critical
  • •Monitor mood and hormonal signals
When to consult a healthcare professional

Routine check-ups remain valuable — track energy, sleep and hormonal signals.

Medical Evidence

How we ground the Body Fat

Grade B · Observational studiesLast reviewed Nov 1, 2025
Named clinical guidelines
  • US Navy Circumference method (Hodgdon & Beckett, 1984)
  • ACE Body Composition classification
References

The Evidence Foundation

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Elements84 brings reviewed health evidence, practical decision tools and plain-English explanations together without presenting educational guidance as diagnosis or treatment.

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  3. Limitations shown beside conclusions
  4. Educational, not diagnostic

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