BMI Calculator

Your body mass index (BMI) is your weight in kilograms divided by the square of your height in meters. The BMI is a concise number typically used to determine if an individual fits in one of the four categories:

BMI Result Chart

< 18.5
Average Weight
18.5 - 25
25 - 30
> 30

BMI Calculator

Height and Weight


The immediate application of a BMI number is seeing how much fat is in the body.

The higher the BMI, the higher the expected fat content in the body. BMI percentages are not perfect for identifying health risks. For instance, a 5’9″ person who weighs 180 lbs is considered overweight. However, if that weight is due to muscle, then the BMI is less indicative of health problems.

BMI is a great initial diagnosis tool if you are having health problems. Further studies will be needed to determine the extent of how your weight affects your health.

body mass index graphic

BMI Ranges


Many people classified as underweight are fairly healthy. However, severe underweight status could cause significant problems that could affect them for life, such as inhibited growth.

A common misconception is that being underweight is due to not eating enough. A good deal of underweight cases are due to previously existing or new medical conditions. Illness, medicine, and genetics can often be the cause of underweight conditions.

If you are looking to put on weight, it is suggested to eat small portions of nutrient-dense food throughout the day. Couple this with strength training, which can help retain healthy calories and add muscle instead of fat.

underweight symbol

Health Risks

Bone loss
Weak immune system
Issues with fertility
Hair loss

Normal Weight

According to BMI, this is the target percentage of body fat. This BMI rating suggests that you would be least inclined to suffer health issues. The BMI is not always an accurate gauge of health, so there can be unseen issues if you have excess fat. According to the Mayo Clinic, while your BMI may hit the target area, you could still be obese, but just not classified as such.

normal weight symbol


It is estimated that 2 in 3 American adults are overweight or obese. Sedentary lifestyles coupled with plentiful amounts of food are often the culprit. Again, BMI only postulates how much fat the body contains. For instance, if you have an elevated muscle mass or excess water, your BMI may classify you as overweight.

over weight symbol

Health Risks

Diabetes (Type 2)
Heart disease
Kidney disease
Nonalcoholic fatty liver disease
Sleep apnea


Almost 33% of all American adults are considered obese. If most of your weight is around your stomach, then you may be at greater risk for various health afflictions.

If considered obese, you may have a large amount of fat not just under the skin, but surrounding the organs. If you want to get rid of this internal fat, you will need to exercise 22 minutes a day each day. Exercise can count as taking a walk or riding a bike.

obese symbol

Health Risks

Gallbladder disease
General pain
Clinical depression
High cholesterol
Coronary heart disease
Pulmonary hypertension

Concerned about your BMI?

Blue Tree Health’s Austin weight loss clinic can help you get your BMI where you think you need it. From lipoden injections to B12 shots and prescription medication, we can develop a plan that suits your needs. Get your BMI under control starting today.

*Results may vary from patient to patient.