Body Mass Index (BMI)
Weight divided by height squared. Still used for general screening and in some enlistment height-weight tables, though the military now screens body composition with WHtR.
Data updated: 2026-08-20 (verified vs primary service regulations)
Formula
BMI = weight (lb) × 703 ÷ height (in)²
Healthy range
Underweight < 18.5 · Normal 18.5–24.9 · Overweight 25–29.9 · Obese ≥ 30.
Military & first-responder angle
The military retired BMI-style height-and-weight tables as the body-composition entry screen on 2026-01-01, but height-weight screening still precedes the WHtR check in most services. BMI is used in NFPA 1580 baseline fitness testing for firefighters.
Calculator
Body Mass Index with the accession context. The Air Force screens roughly BMI 17.5–27.5; the Coast Guard uses 19.0–27.5.
Result
About this calculator
Body Mass Index (BMI) is weight divided by height squared — a quick first-screen for underweight, normal, overweight, or obesity.
The formula
BMI = weight(kg) ÷ height(m)². Under 18.5 underweight, 18.5–24.9 normal, 25–29.9 overweight, 30+ obese.
Frequently asked questions
Q: What BMI ranges do the services use?
A: Accession screens vary: the Air Force is roughly 17.5–27.5, the Coast Guard 19.0–27.5. Confirm with a recruiter.
Q: Is BMI enough on its own?
A: No. In 2026 the services use Waist-to-Height Ratio, not BMI, for in-service composition screening.
Q: Does BMI distinguish muscle from fat?
A: No. A muscular person can show a high BMI with low body fat, which is why services add circumference screens.
How to read the result
BMI is a population screen that works well across groups and poorly on individuals. It was built to describe how weight scales with height in a large sample, so it ignores the thing that most interests a service member: whether the mass is muscle or fat. A trained recruit with a heavy frame can sit in the overweight band with a waist that clears every gate, while a lighter person can sit in the normal band and still carry fat in the abdominal region.
That mismatch is why the in-service screen moved to a waist measure in 2026. BMI retains a role for applicants, because accession standards are published as BMI ranges and a recruiter applies them before any tape comes out. Read this figure as the first filter it was designed to be rather than as a verdict, and always pair it with the waist-to-height ratio to see the part of the picture the two measures disagree about.
Quick answers
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