Body Fat Estimator

Input guidance

Enter the requested measurements in the units shown, then treat the output as an estimate rather than a diagnosis.

How to use this tool

1. Select the sex input used by the estimator.
2. Enter waist, neck, height, and hip measurement where the form asks for it.
3. Review the estimated percentage together with the measurements because small measuring differences can change the result.

Formula or method

• The estimator applies the U.S. Navy-style circumference equations implemented in the tool.
• For male inputs, the equation uses waist minus neck and height; for female inputs, it uses waist plus hip minus neck and height.
• Waist, neck, hip, and height measurements are treated as centimeter values before the logarithmic calculation.
• The result is an approximation and can differ from clinical or laboratory body-composition measurements.

How to interpret the result

Body-fat estimates are sensitive to measurement technique.

• The estimated body-fat percentage is 17.7%, classified here as fit.
• The estimate uses circumference measurements, so tape placement and measurement consistency can materially affect the result.
• It is not equivalent to a clinical body-composition measurement such as DEXA or hydrostatic weighing.