Calculate Your Body Mass Index

Body mass index (BMI) is a measure of body fat based on height and weight that applies to adult men and women.

What the Numbers Mean
BMI below 18.5 – Underweight, 18.5-24.9 – Normal weight, 25-29.9 – Overweight, 30 and higher – Obese.

Note: The BMI may not be accurate for people with greater muscle mass (such as athletes) or in older people and others who have lost muscle mass.

If you are overweight or obese, even a small weight loss (10% of your current weight) lowers the risk of several diseases.

People who are overweight or obese have a greater chance of developing certain cancers—including breast cancer for women over age 50—as well as high blood pressure, high blood cholesterol or other lipid disorders, diabetes, heart disease, and stroke.

Being very underweight – especially if you’ve had rapid or unintentional weight loss – can be a sign of health problems.

A doctor can further assess your personal risk for serious weight-related diseases by considering your BMI, waist size, and other measures of health such as blood sugar levels.

Enter your height and weight below to find your body mass index (BMI). This number is commonly used to judge whether your weight is healthy—or whether extra weight increases your risk for health problems, such as cancer.