BMI Calculator
Calculate your Body Mass Index (BMI) using either Metric or Imperial units.
BMI Classification
| BMI | Category |
|---|---|
| Below 18.5 | Underweight |
| 18.5 – 24.9 | Healthy Weight |
| 25 – 29.9 | Overweight |
| 30 – 34.9 | Obesity Class I |
| 35 – 39.9 | Obesity Class II |
| 40 and above | Obesity Class III |
What Is Body Mass Index (BMI)?
Body Mass Index (BMI) is a simple screening tool used to estimate whether your weight is appropriate for your height. Healthcare professionals use BMI to classify weight into categories such as underweight, healthy weight, overweight, and obesity.
Although BMI does not directly measure body fat, it provides a useful starting point for assessing potential health risks. Your BMI result should always be considered alongside factors such as age, sex, muscle mass, lifestyle, and overall health.
How Is BMI Calculated?
To Calculate BMI, you need your weight in pounds and your height in inches.
The standard BMI formula is:
BMI = (weight ÷ height²) × 703
This math formula is a simple equation that produces a numerical value representing your body mass index.
For children, the process is different because age and sex are considered. Whether you are an adult, child, male, or female, the formula relies on weight measurement, height measurement, pounds calculation, and inches calculation to produce a health metric and numeric assessment.
BMI Categories
The standard weight classification system includes:The obesity range is further divided into:
| BMI | Category |
|---|---|
| Under 18.5 | Underweight |
| 18.5–24.9 | Healthy Weight |
| 25–29.9 | Overweight |
| 30+ | Obesity |
Want to Learn More About BMI?
BMI is a useful health screening tool, but there’s much more to understand about how it’s calculated, its limitations, and how healthcare professionals use it.
Read the complete guide →