Army Body Fat Calculator
Estimate your body-fat percentage with the US Army tape test (Hodgdon-Beckett, DA Form 5500/5501) and see how it compares to the AR 600-9 maximum for your age.
Body fat — Within AR 600-9 limit
0.16%
- AR 600-9 maximum (age 21-27)
- 0.22%
- Margin under limit (pp)
- 6.5
- Method
- Hodgdon-Beckett tape test (DA 5500/5501)
The Army "tape test" uses the Hodgdon & Beckett (1984) circumference equation, evaluated in inches per DA Form 5500 (men) and DA Form 5501 (women). Soldiers above the age-bracketed maximum in AR 600-9 are enrolled in the Army Body Composition Program until they return to standard. The estimate is population-level — typical agreement with hydrostatic weighing is within about ±3-4 percentage points.
How to use this calculator
Pick your sex and enter your age, then measure with a soft tape in inches: height standing barefoot, neck just below the larynx, waist (men: a horizontal line at the navel; women: the narrowest point above the navel). Women also enter hip circumference at the widest point around the buttocks. The calculator returns your body-fat percentage and shows whether it sits at or below the AR 600-9 limit for your age bracket.
How the calculation works
The Army uses the Hodgdon & Beckett (1984) circumference equation, originally derived for the US Navy and adopted into AR 600-9 ("The Army Body Composition Program"). Men: %BF = 86.010 · log10(waist − neck) − 70.041 · log10(height) + 36.76. Women: %BF = 163.205 · log10(waist + hip − neck) − 97.684 · log10(height) − 78.387. All measurements are in inches. The result is then compared against the maximum allowable body-fat percentage in AR 600-9: men 20% (age 17-20), 22% (21-27), 24% (28-39), 26% (40+); women 30%, 32%, 34%, 36% over the same brackets.
Worked example
A 30-year-old soldier, 70 in tall, 36 in waist, 16 in neck: waist − neck = 20, log10(20) = 1.30103, log10(70) = 1.84510, so %BF = 86.010 × 1.30103 − 70.041 × 1.84510 + 36.76 ≈ 19.4%. The AR 600-9 maximum for a male in the 28-39 bracket is 24%, so this soldier is about 4.6 percentage points under the limit — comfortably within standard.
Frequently asked questions
Where do I measure for the Army tape test?
Neck: just below the larynx, tape tilted slightly down at the front. Waist for men: a horizontal line at the level of the navel, taken at the end of a normal exhalation. Waist for women: the natural waist at its narrowest point (usually above the navel). Hip (women only): the widest horizontal circumference around the buttocks. Three measurements are taken at each site and averaged to the nearest half inch, per the procedure on DA Form 5500 / 5501.
What is the maximum body fat allowed in the Army?
Under AR 600-9, men may not exceed 20% body fat at age 17-20, 22% at 21-27, 24% at 28-39, and 26% at 40 or older. Women may not exceed 30%, 32%, 34%, and 36% over the same age brackets. Soldiers who exceed the limit are enrolled in the Army Body Composition Program until they return to standard. These are the pre-2023 thresholds and remain in effect; a 2023 update introducing a single abdominal-circumference formula was deferred for further validation.
Is the Army tape test the same as the Navy method?
Yes — the underlying formula is identical. Both services use the Hodgdon-Beckett (1984) circumference equations developed at the Naval Health Research Center. The procedural details differ (the Army uses DA Form 5500/5501, the Navy OPNAVINST 6110.1) and the maximum allowable percentages by age vary between services and even between branches, but the math that turns tape measurements into a body-fat percentage is shared.
How accurate is the tape test?
Against criterion methods like hydrostatic (underwater) weighing or DEXA, the Hodgdon-Beckett equations agree within roughly ±3-4 percentage points for most adults. They were calibrated on military personnel and are less reliable for very muscular bodies (where neck thickness can pull the estimate down) or for people whose proportions sit outside that calibration range. For tracking change over time the tape test is consistent enough as long as you measure the same way each time.
Do I need to measure in inches?
Yes. The Army tape test is defined in inches on DA Form 5500 (men) and DA Form 5501 (women), and the Hodgdon-Beckett coefficients are calibrated for inches. If you have metric measurements, convert with 1 inch = 2.54 cm before entering them. This calculator expects inputs in inches.
What if my answer is over the AR 600-9 limit?
The calculator simply shows where you stand against the published threshold for your age and sex — it is not an official determination. A soldier flagged over the limit on an actual tape test is enrolled in the Army Body Composition Program with a tailored nutrition and exercise plan until they return to standard. The most actionable response is to recheck the measurement technique (tape level, exhalation, three-measurement average) and consult unit medical or fitness staff.