Body Fat Calculator
Body fat percentage estimate using the US Navy method.
Overview
Estimates your body fat percentage from a few body measurements. It is useful for tracking changes over time and for adding context that weight alone cannot give. It is an estimate, not a clinical measurement.
How it works
The calculator uses the U.S. Navy method, which estimates body fat percentage from body circumference measurements rather than weight. It uses your height and the circumference of your neck and waist (and, for women, your hips), then applies the Navy equation to produce a percentage. Because it relies on tape measurements, accuracy depends on measuring carefully and consistently. Clinical methods such as DEXA scans are more precise, so treat this as a convenient estimate.
How to use it
- Select your sex and choose your units.
- Enter your height.
- Measure and enter your neck and waist (and hips, if prompted).
- Read your estimated body fat percentage.
Examples
Tracking over time
Take the same measurements every few weeks under the same conditions to watch the trend, which is more meaningful than any single reading.
Context for weight
Pair the result with your weight to understand body composition rather than relying on the scale alone.
FAQ
How accurate is it?
Where do I measure?
Why do men and women use different inputs?
Is this a medical assessment?
Is my data uploaded?
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