Army Body Fat Calculator
This calculator is for informational purposes only and is not a substitute for professional medical advice. Consult a healthcare provider for personal health decisions.
US Army AR 600-9 log₁₀ tape measurement method
How Army Body Fat Is Calculated
The US Army uses circumference-based body fat estimation defined in AR 600-9 — distinct from the Navy method used elsewhere. Soldiers must meet maximum body fat percentages that vary by age and sex. This calculator applies the official log₁₀ formulas and compares your result to the applicable standard.
Male: %BF = 86.010 × log₁₀(waist − neck) − 70.041 × log₁₀(height) + 36.76. Measure neck at the narrowest point, waist at the navel, height without shoes — all in centimeters (or inches converted internally).
Female: %BF = 163.205 × log₁₀(waist + hip − neck) − 97.684 × log₁₀(height) − 78.387. Hip measurement is taken at the widest point. Waist plus hip must exceed neck for a valid calculation.
Standards: Male maxima are 20% (ages 17–20), 22% (21–27), 24% (28–39), 26% (40+). Female maxima are 30%, 32%, 34%, and 36% in the same age brackets. If over standard, the calculator shows how many percentage points must be lost to pass.
Tape measurements require consistent technique — same time of day, relaxed abdomen, perpendicular tape. Results differ from DEXA or hydrostatic weighing. For general fitness body fat estimation without military standards, see our Navy body fat calculator.
Examples
| Example | Result |
|---|---|
| Male, age 25, valid measurements | Body fat % + pass/fail vs 22% standard |
| Female, age 30 | Compared to 34% max standard |
| Over standard by 3% | Fat to lose: 3 percentage points |
Frequently asked questions
Different log formulas and measurement sites. Army uses AR 600-9 equations; the Navy method uses a separate formula with different constants.
Maximum allowed body fat depends on age and sex — for example, males 21–27 must be at or below 22%; females 21–27 at or below 32%.
Ensure waist exceeds neck (males) and all measurements are positive. Incorrect tape placement is the most common input error.