BMI calculator
This BMI calculator works out body mass index from your height and weight, in US or metric units. It shows the standard adult weight category and the weight range that gives a BMI from 18.5 to 24.9 at your height. BMI is a quick screening number, not a diagnosis.
- Runs in your browser
- Free, no account needed
- Copy or download the result
Result
Example
Units: US (feet, inches, pounds) Height, feet: 5 Height, inches: 9 Weight, pounds: 160 Height, centimeters: 175 Weight, kilograms: 70
BMI: 23.6 Category: Healthy weight Healthy weight range for this height (BMI 18.5 to 24.9): 125.3 to 168.6 lb Adult categories: Underweight below 18.5, Healthy weight 18.5 to 24.9, Overweight 25 to 29.9, Obesity 30 or more. BMI = weight in kg / (height in m)². It is a screening number for adults 20 and older, not a diagnosis, and it is not used this way for children or teens.
How to use the bmi calculator
- Choose Units: US (feet, inches, pounds) or Metric (cm, kg).
- Fill in the height and weight fields for those units. The other fields are ignored.
- Press Run.
- Read your BMI and category, then use Copy result or Download.
How it works
BMI equals weight in kilograms divided by height in meters squared. US inputs are converted using exact factors for inches and pounds.
The result is rounded to one decimal, and that rounded value sets the category: Underweight below 18.5, Healthy weight 18.5 to 24.9, Overweight 25 to 29.9, Obesity 30 or more.
These categories are for adults 20 and older. Children and teens use age and sex percentiles instead.
BMI does not measure body fat directly, so it is a screening number and not medical advice.
Everything runs in your browser. Your input is not uploaded or stored.
Questions and answers
What is a healthy BMI?
For adults, a BMI from 18.5 to 24.9 is in the healthy weight category.
How is BMI calculated in pounds and inches?
BMI is about 703 times weight in pounds divided by height in inches squared. This tool uses the exact metric conversion instead.
Is BMI accurate for athletes?
BMI does not tell muscle from fat, so muscular people can show a high BMI. Talk to a health professional for a full picture.