Enter your measurements to estimate body fat percentage using the US Navy method.
Estimating body fat by measurement
The US Navy method estimates body fat percentage from a few tape measurements rather than expensive equipment. It compares the circumference of the waist and neck, plus the hips for women, against height, using a formula calibrated against more precise methods.
Its accuracy lives or dies on careful, consistent measuring. A centimeter off at the waist noticeably shifts the result, so measure relaxed and at the same landmarks each time. The figure is a useful trend to track over weeks, not a clinical diagnosis.
The formula
Worked example
A man 175 cm with a 38 cm neck and 85 cm waist estimates around 17% body fat.
How to read your result
The Navy circumference method is a quick estimate that depends heavily on accurate measurements. It is informational and less precise than clinical methods.
Frequently asked questions
- How accurate is it?
- It is a reasonable estimate but sensitive to how carefully you measure.
- Where do I measure?
- Neck below the larynx, waist at the navel, and for women, hips at the widest point.
- Is this a diagnosis?
- No, it is informational only.
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