Advanced Body Fat Calculator
Estimate body fat percentage using the U.S. Navy circumference method with simple measurements and no specialized equipment.
Example body-fat estimate
Example only. Your result depends on your measurements and selected formula.
Calculate Your Body Fat
Enter your measurements below. Male and female versions of the circumference formula use slightly different inputs.
Estimated body fat percentage
Your category will appear here.
This is a formula-based estimate, not a direct measurement.
Why Use a Circumference Method?
This approach adds body measurements that are not included in a standard height-and-weight calculation.
Uses more context
Height, neck, waist, and hip measurements provide more information than weight alone.
Goes beyond BMI
Body-fat estimates can add context when weight-to-height measurements do not tell the full story.
Easy to repeat
Use the same measurement process over time to observe general changes in the estimate.
How It Works
Accurate-looking results still depend on consistent measurement technique.
Select a formula option
The male and female versions use different circumference inputs.
Measure consistently
Keep the tape level and snug without compressing the skin.
Review the estimate
Use the result as general information, not as a diagnosis.
Where to Measure
Neck
Measure around the neck below the larynx, keeping the tape level.
Waist
Use the same location each time and avoid pulling the tape tightly.
Hips
For the female formula, measure around the widest part of the hips and buttocks.
Body-Fat Categories
Category boundaries vary between references. Use them as broad context rather than a definitive assessment.
Essential fat
Very low estimates should be interpreted carefully and not used alone to guide dietary changes.
Athletic or fitness range
These labels are broad reference descriptions and do not measure performance or overall health.
General reference range
A result may fall within a broad reference range while other health factors still require attention.
Body-fat formulas can be affected by measurement error, body shape, age, sex, hydration, and muscle distribution. Professional body-composition methods may produce different results.
Frequently Asked Questions
It is a circumference-based formula that uses height and selected body measurements to estimate body-fat percentage without specialized equipment.
It is an estimate, not a direct measurement. Results can differ from professional methods and can change when measurements are taken differently.
The formula uses a different circumference calculation, which includes hip measurement in addition to height, neck, and waist.
It provides different information. BMI uses height and weight, while this method uses circumference measurements. Neither result should be interpreted alone.
Understand Your Body Composition
Get a simple body-fat estimate and use it as one piece of your broader health picture.
