BMI calculator
Enter your height and weight to see your body mass index to one decimal and the adult category the World Health Organization places it in. BMI describes groups of people rather than one person, and this runs entirely in your browser.
Medically reviewed by Kevin Brandstetter, M.D.Updated September 22, 2026
Your BMI
Enter your height and weight
Your BMI and its category appear here once both are filled in.
A calculator, not a diagnosis.
BMI is a ratio of weight to height that describes groups of people well and any one person poorly. It says nothing about body composition, muscle, where weight is carried, pregnancy, or health. The adult categories do not apply to children or teenagers, and this tool is for adults. A licensed clinician reads a BMI alongside your history, not instead of it.
Methodology
- How this is calculated
- BMI is weight in kilograms divided by height in meters squared. Pounds and feet and inches are converted to kilograms and centimeters first, using the exact definitions of the pound and the inch, so the answer does not depend on which units you type. The result is shown to one decimal, and the category is read from that displayed number, so the panel never prints a number and a category that disagree.
- Where the data comes from
- World Health Organization, Obesity: preventing and managing the global epidemic, WHO Technical Report Series 894 (Geneva, 2000), section 2.3 and Table 2.1. Two labels differ from the table. For 25.0 to 29.9 this page uses the table's umbrella label, “Overweight”, rather than its sub-row label for that range, “Preobese”. Where the table writes “Obese class I”, “Obese class II”, and “Obese class III”, this page writes “Obesity class”, because the noun names a range while the adjective, printed beside your own number, reads as a statement about you.
- Last updated
- September 22, 2026
- What this does not account for
- Body composition, muscle mass, frame, age, sex, ethnicity, pregnancy, and every other fact a clinician weighs. WHO also publishes lower action points for some Asian populations; this tool does not apply them, because choosing which applies to you is a clinical judgment a calculator cannot make.
The adult categories
These are the ranges the World Health Organization uses for adults of any age and either sex. They were drawn from how BMI relates to health risk across large populations, and they describe a range rather than a person.
| BMI | Category |
|---|---|
| Below 18.5 | Underweight |
| 18.5 to 24.9 | Normal range |
| 25.0 to 29.9 | Overweight |
| 30.0 to 34.9 | Obesity class I |
| 35.0 to 39.9 | Obesity class II |
| 40.0 and above | Obesity class III |
What BMI leaves out
Two people with the same height and weight can carry very different amounts of muscle and fat, so they share a BMI without sharing a body. That is why a clinician treats BMI as a starting point, and reads it with waist measurement, blood pressure, labs, and history rather than on its own.
If you are weighing a GLP-1 medication, the GLP-1 eligibility checker compares a BMI with the thresholds that medication labeling is written around, alongside the questions a prescriber asks first.
Nothing here is stored
Your answers stay in your browser. They are not sent to Temi, not saved, not attached to you, and not recorded in any session replay, and closing the tab clears them. Temi knows only that someone opened this tool, the same thing it knows about every page.
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Already taking a medication?
Temi's physicians review renewals for non-controlled medications, usually within 48 hours. A number on this page is not a prescription and does not decide anything.
A licensed physician reviews every request. Nothing on this page is a prescription.