SuperCalc

BMI Calculator for Teens

BMI for teenagers is interpreted differently than for adults. Because teens are still growing and body composition changes rapidly during puberty, health professionals use BMI-for-age percentile charts rather than fixed cutoffs. A teen in the 5th–85th percentile range is considered healthy weight. This calculator computes your standard BMI — but if you are between 13 and 19, the result should be compared against CDC or WHO age-sex percentile charts for accurate classification.

BMI Calculator

Enter your height and weight to calculate your Body Mass Index.

cm
kg

BMI Categories

WHO classification of Body Mass Index ranges.

CategoryBMI Range
Underweight
< 18.5
Normal
18.5 – 24.9
Overweight
25 – 29.9
Obese I
30 – 34.9
Obese II
35 – 39.9
Obese III
40+

Frequently Asked Questions

Why is teen BMI different from adult BMI?
Teens are still growing, and body fat naturally changes during puberty. A 14-year-old boy and a 17-year-old boy at the same height and weight have different health implications. That's why doctors use BMI-for-age percentile charts (CDC in the US, WHO internationally) rather than the fixed adult cutoffs of 18.5/25/30.
What BMI percentile is healthy for a teenager?
Healthy weight: 5th to 85th percentile. Overweight: 85th to 95th percentile. Obese: 95th percentile and above. Underweight: below the 5th percentile. These percentiles compare your BMI to other teens of the same age and sex.
Should I be concerned about my teen's BMI?
BMI is a screening tool, not a diagnosis. If your teen's BMI falls outside the healthy percentile range, discuss it with a pediatrician. Many factors — puberty timing, muscle development, growth spurts — affect teen weight. Avoid fixating on the number; focus on balanced nutrition and activity.

Medical disclaimer: BMI is a screening tool, not a medical diagnosis. It does not measure body fat directly and does not account for muscle mass, bone density, age, sex, or ethnicity. Consult a healthcare provider for personalized health advice.

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