What Is BMI and What Does It Mean?
A complete guide to understanding Body Mass Index and how it is calculated.
Check your Body Mass Index instantly. Enter your height and weight to find out if you're at a healthy weight.
The World Health Organization defines four standard BMI categories for adults aged 18 and over.
Get your BMI result in three simple steps — no account or registration needed.
Select metric (kg/cm) or imperial (lb/ft) depending on your preference.
Type your height and weight accurately for the most precise result.
Click Calculate and see your BMI score and category instantly.
Read what your result means and what steps you can take next.
Understand what BMI means, how it affects your health, and what you can do about it.
A complete guide to understanding Body Mass Index and how it is calculated.
How healthy BMI ranges change as you get older and what the numbers really mean.
Realistic, science-backed strategies to move towards a healthier weight.
BMI does not know whether you have lost muscle or gained fat, and it cannot see what happens to a woman's body through perimenopause and menopause — the weight that settles around the middle without any change in how you eat, the sleep that stops working, the energy that does not come back after a full night.
If the number surprised you, the next question is usually not how much do I weigh but what is happening to me. That is what these guides are for.
Why BMI is not enough · BMI vs body fat percentage · How BMI changes with age