SuperCalc

BMI Calculator for Adults

The standard BMI calculator is designed for adults aged 20 and older. For this age group, the WHO uses fixed category cutoffs (18.5, 25, 30) regardless of age or sex. Enter your weight and height below for an instant reading with visual gauge, category classification, healthy weight range for your height, and BMI Prime value.

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

Is the adult BMI formula different from the teen formula?
The formula (weight/height^2) is the same, but interpretation differs. Adults use fixed cutoffs (18.5/25/30). Teens and children use BMI-for-age percentile charts because their body composition changes during growth. The adult formula applies from age 20.
Does the adult BMI calculator work for elderly people?
The formula works, but interpretation should be adjusted. Research suggests a slightly higher BMI (23–28) may be healthier for adults over 65, as moderate weight provides a buffer against frailty, falls, and illness. Very low BMI in elderly adults is a stronger health concern than moderate overweight.
Is adult BMI the same for all ethnicities?
The formula is universal, but health risks at a given BMI vary by ethnicity. Asian populations develop metabolic complications at lower BMIs — some Asian health guidelines use 23 and 27.5 as overweight and obese cutoffs instead of 25 and 30. Pacific Islanders and Polynesians may be healthier at higher BMIs.

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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