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HEALTH

Body Fat Calculator

Estimate estimated body fat from weight, height, age with the Body Fat Calculator.

Choose a body-fat methodUse the quick BMI estimate or the circumference-based U.S. Navy method.
2 options
ESTIMATED BODY FAT21.24 %

BMI-age-sex method; average range; fat mass 15.9 kg and lean mass 59.1 kg. Educational estimate only; not medical advice.

Body Fat (BMI method)
21.24%
Body Fat Category
average range
Body Fat Mass
15.9 kg
Lean Body Mass
59.1 kg
Ideal Body Fat for Given Age (Jackson & Pollock)
15.4%
Body Fat to Lose to Reach Ideal
4.4 kg
Estimate based on the values shown
MethodSelectable BMI-age-sex and U.S. Navy circumference estimates.

Before you use the result

Educational estimate only; it cannot diagnose a condition or replace advice from a qualified health professional.

CALCULATOR GUIDE

How to use the Body Fat Calculator

Estimate estimated body fat from weight, height, age with the Body Fat Calculator. It includes BMI estimate, U.S. Navy workflows, so choose the one that matches the values you actually know. Use it to understand an educational estimate and the inputs behind it, not as a diagnosis or treatment decision.

Step by step

  1. For the Body Fat, enter weight, height, age, sex, neck circumference. Keep each value in the unit displayed beside its field.
  2. Review the selected Body Fat workflow and inputs, then read estimated body fat in the result panel.
  3. Change one Body Fat assumption at a time to compare scenarios. Use Reset to restore this tool's worked example values.

How the calculation works

Selectable BMI-age-sex and U.S. Navy circumference estimates.

Worked example

In the Body Fat worked example, weight 75 kg, height 175 cm, age 35 years, sex Male produces estimated body fat of 21.24 %. BMI-age-sex method. Review the displayed units before comparing the result.

Understanding the result

The Body Fat reports estimated body fat. Use it to understand an educational estimate and the inputs behind it, not as a diagnosis or treatment decision. Educational estimate only; it cannot diagnose a condition or replace advice from a qualified health professional.

How to check the answer

Check the Body Fat estimate by confirming the units and supported ranges for weight, height, age. Compare estimated body fat with another published method or direct measurement when available, and ask a clinician before using it for a health decision.

Common questions

What does the Body Fat calculate?

Estimate estimated body fat from weight, height, age with the Body Fat Calculator.

Which Body Fat inputs have the biggest effect?

estimated body fat responds directly to weight, height, age, sex, neck circumference. Change one input while holding the others constant to see its effect.

Is the Body Fat result exact?

Educational estimate only; it cannot diagnose a condition or replace advice from a qualified health professional. Recheck weight, height, age and use estimated body fat only for a decision where that level of precision is appropriate.

Formula tests, limits, sources, and guide registry updated September 1, 2026.
INTERPRET THE RESULTRead the health guideCheck assumptions, limitations and comparison methods →