Body Fat Calculator

How this tool works

Uses the circumference equations commonly called the U.S. Navy method, with inch conversion before logarithms. Tape placement affects the result. This is not an official military body-composition assessment. For adults aged 20–100. These are educational estimates, not diagnoses, treatment targets or medication-dosing guidance. They are not designed for children, pregnancy or breastfeeding; body composition and health conditions can make the estimates unsuitable. Discuss personal concerns with a qualified clinician. Inputs stay in your browser.

Research on circumference-based body-fat prediction