Army Body Fat Calculator
Enter height, neck, waist (and hip for women) to estimate body fat % with the U.S. Army tape method.
Input Data
Results
At a glance:U.S. Army formula (inches): men = 86.010×log10(waist−neck) − 70.041×log10(height) + 36.76; women = 163.205×log10(waist+hip−neck) − 97.684×log10(height) − 78.387. This tool takes cm and converts to inches.
Formula
height_in = heightCm ÷ 2.54; neck_in = neckCm ÷ 2.54; waist_in = waistCm ÷ 2.54; hip_in = hipCm ÷ 2.54.
Men: %BF = 86.010×log10(waist_in − neck_in) − 70.041×log10(height_in) + 36.76.
Women: %BF = 163.205×log10(waist_in + hip_in − neck_in) − 97.684×log10(height_in) − 78.387.
How to Use
- Enter height, neck and waist in cm; women also add hip.
- Get the estimated body fat % instantly.
Case Studies
Male 175cm / neck 38 / waist 85
height=68.9in, neck=15.0in, waist=33.5in.
%BF = 86.010×log10(18.5) − 70.041×log10(68.9) + 36.76 ≈ 17.5%.
FAQ
Why measure neck?
Neck circumference removes upper-body non-fat mass; it is the key variable that distinguishes muscle from fat in the Army formula.
How does it compare to BMI?
The tape method uses measured circumferences and is usually closer to actual body fat than a BMI estimate, though still less precise than calipers or DXA.
Do men need hip?
The male formula uses only height, neck and waist; hip is for women only and does not affect male results.
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References
Content reviewed by the Calculatorism editorial team. Results are for reference only; please refer to the relevant authorities for the official figures.