The body mass index (BMI) is the most common tool used to help determine if you are at a healthy weight for your height, and estimating your risk for developing health issues such as heart disease, diabetes, and cancer.
Because the calculation used to estimate BMI doesn’t take your age, sex, or muscle mass into account, it does have limitations. However, it is still useful as it can be calculated quickly at home without the use of expensive technology, tools, or imaging.
Knowing your BMI can be helpful as studies show that there is a steep increase in the risk of health complications as BMI increases over 25. The good news, however, is that even modest weight loss of 5-10% can improve issues such as hyperglycemia, high blood pressure, HIGH cholesterol, obstructive sleep apnea, and depression. And there is often greater improvement seen with even more weight loss.
Our calculator is a quick and easy way to find your BMI and the corresponding BMI weight category for adults ages 20+.
Underweight: Less than 18.5
Normal weight: 18.5 – 24.9
Overweight: 25 – 29.9
Class I Obesity (mild): 30 – 34.9
Class II Obesity (moderate): 35 – 39.9
Class III Obesity (severe): Over 40
Who should not use this calculator?
Due to normal amounts of body fat changes in kids and teens, anyone under the age of 20 should not use this calculator. You can determine a child’s BMI percentile by using the CDC’s online calculator here.
Pregnant women should also not use this calculator as a certain amount of weight gain is necessary for the health of both mom and baby. If you’re pregnant and concerned about your weight, please talk with your doctor.