Check Your Body Mass Index Online
Use our free BMI calculator to check your Body Mass Index in seconds.
BMI Calculator
Check your Body Mass Index using metric or imperial units. Get your BMI score, weight category, BMI Prime, ideal weight range, and how much weight you may need to gain or lose to reach a healthier range.
Your Results
Enter your age, gender, height, and weight to calculate your BMI and view your detailed result.
Height: —
Weight: —
What this means
- Use the calculator to get your result.
- Your BMI category will appear here after calculation.
- This tool is best used as a general screening guide.
BMI Chart for Adults
Use this chart to quickly understand where your BMI falls.
| Category | BMI Range |
|---|---|
|
Underweight
|
Below 18.5 |
|
Healthy Weight
|
18.5 – 24.9 |
|
Overweight
|
25 – 29.9 |
|
Obesity Class 1
|
30 – 34.9 |
|
Obesity Class 2
|
35 – 39.9 |
|
Obesity Class 3
|
40+ |
These BMI categories apply to most adults age 20 and older.
How to Calculate BMI
BMI is calculated by dividing your weight by your height squared. The formula changes slightly depending on whether you use metric or imperial units.
Metric Formula
BMI = weight (kg) ÷ height² (m²)
Example: If you weigh 70 kg and your height is 1.75 m, your BMI is 22.9.
Imperial Formula
BMI = [weight (lb) ÷ height² (in²)] × 703
Example: If you weigh 154 lb and your height is 5 ft 9 in, your BMI is about 22.7.
FAQs
BMI stands for Body Mass Index. It is a simple calculation based on your height and weight that helps estimate whether your weight falls into a healthy range.
BMI is calculated by dividing weight by height squared. In metric units, the formula is weight in kilograms divided by height in meters squared.
For most adults, a healthy BMI falls between 18.5 and 24.9.
No. BMI is useful as a screening tool, but it does not directly measure body fat or muscle. It may not reflect health accurately for every person.
The standard BMI formula is the same for adult men and women, but body composition can still vary.
BMI can be misleading in some cases, especially for athletes, older adults, and people with unusually high muscle mass or different body compositions.
For most adults, the general healthy range is 18.5 to 24.9.
BMI does not directly measure body fat percentage, fat distribution, muscle mass, or overall fitness.