Where you fall on the BMI scale
The pointer marks your BMI; the highlighted band is your category. Updates as you change the inputs.
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BMI Calculator
Find your body mass index from your height and weight, and see exactly where you land on the underweight, normal, overweight, and obese scale.
Your BMI
24.5
Normal weight
Healthy weight range—
Height—
Weight categoryNormal
How it works
Body Mass Index (BMI) is a simple ratio of weight to height that screens for underweight, healthy weight, overweight, and obesity. It is the most widely used quick check because it needs only two numbers you already know.
The formula
Metric: BMI = weight(kg) ÷ height(m)²
US: BMI = 703 × weight(lb) ÷ height(in)²
US: BMI = 703 × weight(lb) ÷ height(in)²
BMI categories (adults)
| Category | BMI range |
|---|---|
| Underweight | Below 18.5 |
| Normal weight | 18.5 – 24.9 |
| Overweight | 25.0 – 29.9 |
| Obese | 30.0 and above |
Good to know
- BMI does not separate muscle from fat, so athletes may read high without excess fat.
- It is a screening tool, not a diagnosis. Pair it with waist size and body-fat percentage for a fuller picture.
- Children and teens use age- and sex-specific BMI percentiles instead of these fixed cut-offs.
Frequently asked questions
What is a healthy BMI range?
For most adults, a BMI from 18.5 to 24.9 is considered healthy. Under 18.5 is underweight, 25–29.9 is overweight, and 30 or above is obese.
Is BMI accurate for everyone?
It works well across populations but not for every individual. Very muscular people can read as overweight, and it can miss excess fat in older adults with low muscle mass.
How is BMI calculated?
Divide your weight in kilograms by your height in metres squared. In US units, multiply 703 by pounds and divide by inches squared.