Health and Fitness

Body Fat Calculator

Estimate body fat percentage from circumference measurements using sex-specific measurement inputs.

Preparing Body Fat Calculator

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Input

Choose the matching sex-specific measurement mode, then enter the listed circumference and height values as carefully as possible. This tool shows the result instantly without step-by-step output.

Input summary

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How to use Body Fat Calculator

Measure the listed body areas consistently, enter them in the correct mode, and the calculator will estimate body fat percentage from those circumferences.

What this calculator is for

This calculator is for a quick body-composition estimate when you do not have access to direct methods such as DEXA, hydrostatic testing, or lab-grade devices. It is useful for trend tracking, but it remains an estimate built from tape measurements.

Tips

Measure in the same spots every time if you want to compare results from month to month.
Keep the tape snug but not tight, because pulling the tape too hard can distort the estimate.
Small measurement errors can move the result noticeably, so recheck the numbers before calculating.

Formula used

This calculator uses the U.S. Navy circumference method. The equations are defined in inches, so centimeter inputs are converted first before the logarithm formula is applied.

Men: % body fat = 86.010 × log10(waist − neck) − 70.041 × log10(height) + 36.76.
Women: % body fat = 163.205 × log10(waist + hip − neck) − 97.684 × log10(height) − 78.387.
Because this is a tape-measure estimate, even small measuring differences can move the result.