BMI Calculator
Calculate your Body Mass Index (BMI) using your height and weight. Get your BMI value and the standard adult BMI category associated with it.
Calculate Your BMI
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What Is BMI?
Body Mass Index, commonly called BMI, is a calculation that compares a person's weight with their height. It is commonly used as a screening measure to place adults into broad weight categories.
Our BMI calculator allows you to calculate BMI using either metric units or US units. Enter your height and weight and the calculator will provide your BMI value and the corresponding standard adult category.
How Is BMI Calculated?
For metric measurements, BMI is calculated by dividing weight in kilograms by height in metres squared.
BMI = weight (kg) ÷ height² (m)
For example, a person weighing 70 kg and measuring 1.75 metres tall has a BMI of approximately 22.9.
Adult BMI Categories
| BMI | Category |
|---|---|
| Below 18.5 | Underweight |
| 18.5 – 24.9 | Healthy weight |
| 25.0 – 29.9 | Overweight |
| 30.0 or higher | Obesity |
Metric BMI Calculation
To calculate BMI using metric units, enter your weight in kilograms and height in centimetres. The calculator converts centimetres to metres before applying the BMI formula.
US BMI Calculation
If you use US units, enter your height in feet and inches and your weight in pounds. The calculator converts those measurements before calculating BMI.
What Does a BMI Number Mean?
BMI categories provide a general screening framework for adults. A BMI value by itself does not measure body fat directly and does not provide a complete picture of an individual's health.
Factors such as muscle mass, age, sex, body composition and other health characteristics can affect how BMI should be interpreted.
Is BMI the Same for Everyone?
The standard BMI categories shown by this calculator are intended for adults. BMI is interpreted differently for children and teenagers because their bodies are still growing and BMI is generally assessed using age- and sex-specific growth charts.
Why Use a BMI Calculator?
- Quickly calculate your BMI from height and weight.
- Use either metric or US measurements.
- See the standard adult BMI category associated with your result.
- Understand the basic BMI formula.
- Use the result as a general screening measurement.
Frequently Asked Questions
For adults, a BMI from 18.5 to 24.9 is commonly classified as the healthy-weight range in the standard BMI categories.
For adults, a BMI from 25.0 to 29.9 falls within the standard overweight category.
For adults, a BMI of 30.0 or higher falls within the standard obesity category.
BMI is a screening measure rather than a direct measurement of body fat or overall health. It can be useful as one measurement, but it does not account for every individual characteristic.
Yes. Select Metric, enter your weight in kilograms and height in centimetres, then click Calculate BMI.
Yes. Select US Units and enter your height in feet and inches and your weight in pounds.
