Use adult cutoffs consistently
The CDC adult categories apply from age 20. Children and teens require age- and sex-specific percentiles, so this worksheet deliberately does not classify them.
Adult weight screening worksheet
Read BMI as a range, not a verdict.
Calculate adult BMI, the CDC category, a height-specific reference weight range, BMI Prime, Ponderal Index and waist-to-height ratio. The extra measures make the result more useful without pretending that height and weight alone describe health.
Adult tool only. It is not designed for children, pregnancy or diagnosis. For a repeatable waist reading, keep the tape level, snug but not compressing, and measure after a normal exhale.
Interpretation guide
What the number can—and cannot—tell you
BMI is useful because it is simple and standardized. It is limited for the same reason: it does not directly measure fat, muscle, bone, fitness or health.
Put composition beside weight
A muscular person and a person with lower lean mass can share the same BMI. Waist, trends, clinical measurements and health history can change the interpretation.
Track repeatable trends
If monitoring weight or waist, use similar clothing, equipment and time of day. A single reading is less informative than a consistent pattern.
Formula
BMI = weight in kilograms ÷ height in meters squared. BMI Prime divides BMI by 25; Ponderal Index divides weight by height cubed.
Reference range
The displayed weight interval is the weight implied by BMI 18.5 through 24.9 at the entered height. It is not a personalized prescription.
Medical context
Unexpected weight change, eating concerns or questions about an individual result belong with a qualified healthcare professional.
Simple by design
Three steps to a clearer number.
Enter your details
Use realistic values in each field. You can change them anytime.
Calculate instantly
The formula runs locally, so there is no account or waiting time.
Use the result
Treat the answer as a practical estimate for your next decision.