Body Fat Percentage Calculator – Estimate Your Body Fat
Body fat percentage is the share of your total weight made up of fat tissue. Unlike BMI it separates fat from muscle, bone and organs, which makes it a far more useful number when the goal is changing how you look rather than simply what the scale says.
You can estimate it at home with a tape measure — no scales, tanks or clinics required. Enter either circumferences for the US Navy method, or just your basic stats for a BMI-based estimate.
How The Two Methods Differ
US Navy tape method. Developed from work by Hodgdon and Beckett, it uses neck and waist measurements (plus hip for women) alongside height. Given careful measuring it typically lands within roughly 3% of underwater weighing for the average adult.
BMI-based estimate. The Deurenberg equation plugs age, sex and BMI into a formula. It needs no tape measure but carries wider error bars, especially for very muscular or very lean physiques.
Either way the absolute number matters less than the trend. Measure under the same conditions every two weeks and watch which direction the line moves.
Reference Ranges
Women carry more essential fat than men for hormonal reasons, so the ranges differ by sex. Single-digit body fat is unsustainable long term for men, and dropping below essential levels for women disrupts normal endocrine function.
If you also want calorie targets to reach those ranges, plug your stats into the TDEE calculator and then set grams with the macro calculator.
Frequently Asked Questions
What counts as a healthy body fat range?
It depends on sex and how lean you want to be. Athletic ranges sit roughly at 6–13% for men and 14–20% for women, while "fit but sustainable" lands nearer 14–17% and 21–24%. Essential fat is lower for men than women.
Can I lose body fat without losing weight?
Yes — that is body recomposition. Eat near maintenance with high protein and train hard, and fat drops while muscle slowly replaces it. The scale may barely move while your body fat percentage falls.
How accurate are home methods?
Expect within about 3–5% of a DEXA scan. Skinfold calipers done well, hydrostatic weighing and DEXA are more precise, but consistency with any single method beats switching between several.
When should I measure?
First thing in the morning after using the bathroom, before breakfast. Stand relaxed, exhale normally, and keep the tape level and snug rather than pulled tight.
Could smart scales replace this?
Bioimpedance scales are convenient but sensitive to hydration; readings swing several points across a single day. Use them for long-term averages, or tape measures for repeatable comparisons.
Results come from published population equations and are estimates only — they are not medical advice. See our disclaimer.
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TDEE Calculator – Calculate Your Total Daily Energy Expenditure
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Macronutrient Calculator – Calculate Your Macros for Fitness Goals
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BMI Calculator – Free Body Mass Index Calculator
Instant WHO category plus your healthy weight range.
Maintenance Calorie Calculator – Find Your Daily Calorie Maintenance Level
The number your weight holds steady at.