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Body Fat Calculator

Estimate body fat percentage using circumference method or BMI based estimate.

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Formula

Uses Navy circumference method or BMI based estimate depending on method selection.

Choose method and provide required body measurements to estimate body fat.

Worked Example

Waist, neck, and height values can estimate body fat percentage.

Estimating Body Fat Percentage

Body fat percentage is a more meaningful health metric than weight or BMI alone because it distinguishes between fat mass and lean mass (muscle, bone, organs).
  • The Navy circumference method uses neck, waist, and hip measurements with a logarithmic formula to estimate body fat
  • Healthy body fat ranges: males 10% to 20%, females 18% to 28%. Athletes may be lower, and essential fat minimums apply
  • The BMI-based estimate is less accurate but requires fewer measurements. It derives body fat from BMI, age, and gender
  • For the most accurate results with the circumference method, measure at the same time of day in similar conditions each time

Body fat calculators provide estimates. For clinical accuracy, consider DEXA scans, hydrostatic weighing, or professional calipers.

You can also calculate changes using our BMI Calculator, Ideal Weight Calculator, Calorie Calculator or TDEE Calculator.

Frequently Asked Questions

Which method is more accurate for body fat?

The Navy circumference method is generally more accurate than BMI-based estimation because it uses direct body measurements rather than deriving fat from weight and height alone.

Do women need a hip measurement?

Yes. The Navy method for females uses waist, hip, and neck measurements in its formula. The male formula uses only waist and neck.

What is a healthy body fat percentage?

For adult males, 10% to 20% is considered healthy. For adult females, 18% to 28% is healthy. Essential fat (the minimum needed for health) is approximately 3% for males and 12% for females.

Is body fat percentage better than BMI?

For individual health assessment, yes. Body fat percentage distinguishes between fat and muscle, while BMI treats all weight equally. A muscular person can have a high BMI but healthy body fat.

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