Army Body Fat Calculator
Estimate body fat with the U.S. Army (AR 600-9) tape method and check the standard.
Results update as you type.
About this calculator
The U.S. Army body fat calculator uses the AR 600-9 circumference (tape) method to estimate body-fat percentage from height and a few measurements. Men use abdomen minus neck; women use waist plus hip minus neck. It also compares the result against the Army maximum allowable body fat for your age and sex.
The formula works on the logarithm of a circumference difference. For a man 70 in tall with a 34 in abdomen and 16 in neck, %BF = 86.010 × log10(34 − 16) − 70.041 × log10(70) + 36.76 ≈ 15.5%. Against the maximum of 22% for a soldier aged 21–27, that is within standard. Women use %BF = 163.205 × log10(waist + hip − neck) − 97.684 × log10(height) − 78.387, with every measurement in inches.
The maximum allowable body fat rises with age — for men 20% at 17–20 up to 26% at 40+, and for women 30% up to 36% across the same bands — and the tool flags whether you pass. Measure the abdomen at the navel and the neck just below the larynx; women add the hips at their widest. The tape method is a practical screen, not a lab-grade measurement like DEXA, and this tool is for reference, not official assessment.
Frequently asked questions
What is the AR 600-9 formula?
For men, %BF = 86.010 × log10(abdomen − neck) − 70.041 × log10(height) + 36.76. For women, %BF = 163.205 × log10(waist + hip − neck) − 97.684 × log10(height) − 78.387, with all measurements in inches.
What is the maximum allowable Army body fat?
It rises with age. For men it is 20% (17–20), 22% (21–27), 24% (28–39) and 26% (40+); for women 30%, 32%, 34% and 36% across the same bands. The calculator flags whether you are within the limit.
How is this different from the Navy method?
Both use tape measurements, but the constants differ and the Army compares your result to service body-composition standards. Neither replaces a lab method like DEXA for precision.
What is the Army tape test?
It estimates body fat from a few tape measurements instead of calipers or a scale. Men measure neck and abdomen; women measure neck, waist and hip, all in inches, and the AR 600-9 formula converts them to a body-fat percentage.
How do I pass the Army body fat standard?
Your estimated body fat must be at or below the maximum for your age and sex — for example 22% for a man aged 21–27. The calculator flags whether your result is within the limit.
Where exactly do I take the measurements?
Men measure the abdomen at the navel and the neck just below the larynx; women measure the natural waist at its narrowest point, the hips at their widest, and the neck. Average repeated measurements and round as the regulation specifies.
How accurate is the tape method?
It is a practical screening estimate and can differ from lab methods like DEXA by several points. It tends to be least accurate for very muscular or very lean people, which is why it is a service standard rather than a precise measurement.
API — use this calculator from code
Call this calculator as a free JSON endpoint — no key required. Send the field values below as query parameters or JSON. Read the full API docs →
Endpoint
GET https://calculator.free/api/v1/army-body-fat/curl
curl "https://calculator.free/api/v1/army-body-fat/?sex=male&age=25&units=imperial&height=70&neck=16&waist=34"JavaScript fetch()
const r = await fetch(
"https://calculator.free/api/v1/army-body-fat/?" + new URLSearchParams({
"sex": "male",
"age": "25",
"units": "imperial",
"height": "70",
"neck": "16",
"waist": "34"
}));
const data = await r.json();
console.log(data.results);Results are estimates for general guidance only, not financial, medical or tax advice.