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Body Fat Calculator
The US Navy circumference method. A tape measure, three numbers, and an honest margin of error.
01
Method
02
About you
03
Measurements
Just below the larynx, tape sloping slightly down at the front.
At the navel, relaxed — do not pull the tape tight or suck in.
Estimated body fat
17,7%
Fitness · US Navy
Lean body mass
65,8kg
Fat mass
14,2kg
Sum of folds
—navy method
Body density
—n/a
Every method here is an estimate. Skinfolds land within roughly ±3% of a hydrostatic result when the folds are taken consistently; the circumference method is nearer ±4%. Site technique matters more than which formula you pick — same time of day, same person taking the folds, same calipers.
Use 17,7% in the TDEE calculatorA known body fat % unlocks Katch-McArdle, which works from lean mass instead of total weight.