Use our free Body Fat Calculator to get a clear estimate in seconds. Enter your values and see an instant result. Create a free account if you want your inputs saved for next time.
How to use this body fat calculator
- Enter each requested value using the units displayed beside the field.
- Select any options that match your situation, then choose Calculate result.
- Review the main answer and supporting values. Change any input to compare another scenario.
The formula
The Navy method uses logarithmic equations based on waist, neck, height, and—when applicable—hip circumference.
The calculator uses the full precision of your inputs and rounds only the values shown on screen. This helps avoid compounding rounding errors.
Worked example
A 180 cm man with a 90 cm waist and 40 cm neck has an estimated body fat near 19%.
Keep in mind: This result is an estimate for planning and education. It does not replace personalized financial, medical, legal, or other professional advice.