What is a body fat?
The US Navy circumference method estimates body fat percentage from selected body measurements. Accurate, consistent tape placement matters, and this estimate can differ from results obtained with DEXA or other clinical methods. It is intended as a rough screening estimate, not a diagnosis.
Formula and calculation method
The US Navy method uses logarithms of height and waist, with neck and (for women) hip circumference, in sex-specific equations.
The result is only as reliable as the inputs and assumptions. This tool is educational and does not replace professional financial, medical, legal or academic advice.
How to use this calculator
- Enter the values requested in the calculator.
- Review the result panel; it updates when an input changes.
- Change one assumption at a time to compare scenarios.
- Check the formula and limitations before acting on the estimate.
Frequently asked questions
Is this body fat calculator free?
Yes. You can use this calculator in your browser without creating an account.
How accurate is the result?
It applies the displayed formula to the values you provide. Real-world outcomes can differ because of fees, changing rates, individual circumstances or rules not represented in this estimate.
Are my inputs stored?
No. The calculation runs locally in your browser and the values are not submitted to FastSEOHub.