Online Calculators
Most Used CalculatorsMath CalculatorsDate and Time CalculatorsConversion CalculatorsStatistics CalculatorsFinance CalculatorsHealth CalculatorsEducation CalculatorsAll Calculators

Health Calculators

Body Fat Calculator

Use this body fat calculator to review an educational health calculation for body fat.

Primary answer
Estimated body fat
Inputs to verify
Age, Sex used by equation, and Height
Use type
Use as an estimate that depends on assumptions.
Keyword intent
body fat calculator

Calculator

Body Fat Calculator

Calculates estimated body fat from age, sex used by equation, height. Defaults are filled in so you can review a working example before changing inputs.

years

Adult-only estimate; this calculator does not support children, pregnancy, or clinical body-composition assessment.

Choose the published circumference-equation coefficient set used for the estimate.

Use total inches when height unit is in, or centimeters when height unit is cm.

Choose inches or centimeters.

More inputs6 additional assumptions

Use the same circumference unit for neck, waist, and hip.

For the male coefficient, use abdomen at navel; for the female coefficient, use waist as specified by the source method.

Required for the female coefficient and ignored by the male coefficient.

Choose inches or centimeters for all circumference fields.

Weight is used only to estimate fat mass and lean mass from the body-fat percentage.

Choose pounds or kilograms.

Result

Result reflects the current submitted inputs.

  • Risk B
  • Reviewed 2026-05-26
  • 3 sources
Estimated body fat15.5%
Estimated fat mass12.6 kg
Estimated lean mass69 kg
Estimate noteAdult tape-measure estimate only; not a DXA result, diagnosis, military compliance decision, or medical advice.

Breakdown

Height used
70 in
Neck used
16 in
Waist used
34 in
Weight used
81.6466 kg
Equation coefficient
male
  • This calculator is for adult educational estimates only and is not medical advice.
  • The output is a tape-measure estimate, not a DXA, hydrostatic weighing, or clinical body-composition assessment.
  • Measurement location, tape tension, posture, hydration, and body proportions can materially affect the result.
  • The male coefficient uses abdomen minus neck; the female coefficient uses waist plus hip minus neck.
  • No intermediate rounding is applied; display output rounds body-fat percent and masses for readability.

Accuracy notes

Risk level
B
Reviewed
2026-05-26
Sources
3
Primary result
Estimated body fat

Formula logic is kept in a pure calculator module with fixtures, source notes, and page-visible assumptions.

Related calculators

Categories

What the result means

Use Estimated body fat as the headline answer for body fat. Circumference-estimated body fat percentage rounded to one decimal for display. Treat the result as educational context, then read the limitations and assumptions before discussing it with a professional. Use estimated fat mass, estimated lean mass, and estimate note to explain why estimated body fat moved when an input changed. Record the inputs you used and verify any health concern with a qualified professional.

Estimated body fatCircumference-estimated body fat percentage rounded to one decimal for display.
Estimated fat massApproximate fat mass from entered body weight and estimated body-fat percentage.
Estimated lean massApproximate non-fat mass from entered body weight and estimated body-fat percentage.
Estimate noteVisible adult-use limitation and medical disclaimer.

Use the result this way

  1. Start with Estimated body fat, then use supporting outputs only to explain the primary answer.
  2. Verify age, sex used by equation, and height before copying the result.
  3. Choose the mode or method first because it can change which formula is applied, keep units consistent with the labels shown in the form, and stay within the documented minimum and maximum ranges.
  4. Record the inputs you used and verify any health concern with a qualified professional.

User job

How to use this calculator

Use Body Fat Calculator when you need estimated body fat, then use estimated fat mass and estimated lean mass to check the context for general wellness education and preparing for a professional conversation.

Best for

  • Understanding a formula-based estimate
  • Seeing which inputs drive a health-related output
  • Reviewing a default example before entering your own age and sex used by equation.

Check before relying

  • Health formulas can be population-specific; do not use the result as diagnosis or treatment advice.
  • This calculator is for adult educational estimates only and is not medical advice.
  • The output is a tape-measure estimate, not a DXA, hydrostatic weighing, or clinical body-composition assessment.
  • Source context: Frontiers in Physiology, reviewed 2026-05-26.

Next useful step

  • Lean Body Mass CalculatorUse next when the body metric task needs estimated lean body mass instead of estimated body fat.
  • BMR CalculatorUse next when the body metric task needs estimated BMR instead of estimated body fat.
  • Calorie CalculatorUse next when the body metric task needs estimated maintenance calories instead of estimated body fat.

Formula

Uses the U.S. Navy/Hodgdon-Beckett circumference equation after normalizing measurements to inches. Key assumptions: This calculator is for adult educational estimates only and is not medical advice. The output is a tape-measure estimate, not a DXA, hydrostatic weighing, or clinical body-composition assessment. Measurement location, tape tension, posture, hydration, and body proportions can materially affect the result.

  • Uses the U.S. Navy/Hodgdon-Beckett circumference equation after normalizing measurements to inches.
  • This calculator is for adult educational estimates only and is not medical advice.
  • The output is a tape-measure estimate, not a DXA, hydrostatic weighing, or clinical body-composition assessment.
  • Primary source context: Frontiers in Physiology.

Inputs

Enter age, sex used by equation, height, and height unit for general wellness education and preparation for a professional conversation. Before calculating, choose the mode or method first because it can change which formula is applied, keep units consistent with the labels shown in the form, and stay within the documented minimum and maximum ranges. Age: Adult-only estimate; this calculator does not support children, pregnancy, or clinical body-composition assessment. Sex used by equation: Choose the published circumference-equation coefficient set used for the estimate. Height: Use total inches when height unit is in, or centimeters when height unit is cm.

AgeAdult-only estimate; this calculator does not support children, pregnancy, or clinical body-composition assessment.
Sex used by equationChoose the published circumference-equation coefficient set used for the estimate.
HeightUse total inches when height unit is in, or centimeters when height unit is cm.
Height unitChoose inches or centimeters.
Neck circumferenceUse the same circumference unit for neck, waist, and hip.
Waist or abdomen circumferenceFor the male coefficient, use abdomen at navel; for the female coefficient, use waist as specified by the source method.
Hip circumferenceRequired for the female coefficient and ignored by the male coefficient.
Circumference unitChoose inches or centimeters for all circumference fields.
WeightWeight is used only to estimate fat mass and lean mass from the body-fat percentage.
Weight unitChoose pounds or kilograms.

Example

Using the default inputs, Body Fat Calculator returns estimated body fat of 15.5%. Adjust age, sex used by equation, height, and height unit to match your own scenario.

FAQ

How is estimated body fat calculated here?

Uses the U.S. Navy/Hodgdon-Beckett circumference equation after normalizing measurements to inches. The first assumption to check is: This calculator is for adult educational estimates only and is not medical advice.

What does Estimated body fat mean for body fat?

Treat the result as educational context, then read the limitations and assumptions before discussing it with a professional. Secondary values such as estimated fat mass, estimated lean mass, and estimate note are there to explain the primary answer, not to replace it.

What should I enter for Age?

Adult-only estimate; this calculator does not support children, pregnancy, or clinical body-composition assessment. Use years for this field. Choose the mode or method first because it can change which formula is applied, keep units consistent with the labels shown in the form, and stay within the documented minimum and maximum ranges.

How does Sex used by equation change estimated body fat?

Choose the published circumference-equation coefficient set used for the estimate. Changing it can alter estimated body fat because the formula uses the submitted inputs together. Also compare measurement method, formula population, age range, units, sex or activity assumptions, and clinical context.

Why does the body fat example show 15.5% for estimated body fat?

The default inputs produce 15.5% for estimated body fat. Treat that as a format and scale check, then replace every default value with your own inputs.

Can the body fat result diagnose or prescribe anything?

No. Use it as educational context only. Health formulas can depend on population, measurement method, age range, and clinical context.

Sources

Last reviewed: 2026-05-26

  • Reviewed 2026-05-26 · Source 2023-06-07
    Body composition changes during 8 weeks of military training are not accurately captured by circumference-based assessmentsFrontiers in Physiology. Male and female circumference equations, measurement variables, adult limitation context, and error/limitation disclosure.
    Scope
    Peer-reviewed article from U.S. Army Research Institute of Environmental Medicine authors reporting circumference-based equations and limitations against DXA.
    Supports
    Male and female circumference equations, measurement variables, adult limitation context, and error/limitation disclosure.
  • Reviewed 2026-05-26 · Source 1992
    Body Composition and Physical Performance: Introduction and BackgroundNational Academies Press / NCBI Bookshelf. Use of height and neck/waist/hip circumference variables for military-derived body-fat estimates and limitations of anthropometric methods.
    Scope
    Military body-composition background, including Navy circumference method variables and limitations.
    Supports
    Use of height and neck/waist/hip circumference variables for military-derived body-fat estimates and limitations of anthropometric methods.
  • Reviewed 2026-05-26 · Source 1992
    Body Composition In The Military Services: Standards And MethodsNational Academies Press / NCBI Bookshelf. Risk framing and explanation that circumference estimates are screening methods rather than direct body-composition measurement.
    Scope
    Review of military service body-composition standards and circumference methods.
    Supports
    Risk framing and explanation that circumference estimates are screening methods rather than direct body-composition measurement.

Disclaimer

This health calculator is for educational body-metric estimates only. It does not diagnose, prescribe diet or treatment, or replace individualized advice from a qualified health professional.