Body Fat Calculator

Estimate body fat percentage with the US Navy method.

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About the Body Fat Calculator

Estimate your body fat percentage with the US Navy method, which needs only a tape measure. It is often more useful than BMI because it considers where you carry weight.

What to measure

  • Height
  • Neck, just below the larynx
  • Waist at the navel (men) or narrowest point (women)
  • Hips at the widest point (women only)

Tip

Measure in the morning, keep the tape level and snug but not tight, and take the average of two readings for best consistency.

How to use Body Fat Calculator

  1. Enter your values. Units and defaults are shown beside each field.
  2. Press Calculate (results also update as you type once calculated).
  3. Read the result and the step-by-step breakdown with the formula used.
  4. Copy the result or reset to start again.

Frequently asked questions

How accurate is this calculator?

Calculations use the standard formulas shown on the page, computed in full precision and rounded only for display. The result is only as accurate as the inputs and assumptions listed.

Is this medical advice?

No. Health calculators give general estimates for information only and are not a diagnosis. Speak to a qualified health professional about your situation.

Is it free?

Yes. All tools are free to use without an account.