The Body Mass Index (BMI) Calculator can be used to calculate BMI value and corresponding weight status while taking age into consideration. Use the "Metric Units" tab for the International System of Units or the "Other Units" tab to convert units into either US or metric units. Note that the calculator also computes the Ponderal Index in addition to BMI, both of which are discussed below in detail.

BMI is a measurement of a person's leanness or corpulence based on their height and weight and is intended to quantify tissue mass. It is widely used as a general indicator of whether a person has a healthy body weight for their height. Specifically, the value obtained from the calculation of BMI is used to categorize whether a person is underweight, normal weight, overweight, or obese depending on what range the value falls between. These ranges of BMI vary based on factors such as region and age and are sometimes further divided into subcategories such as severely underweight or very severely obese. Being overweight or underweight can have significant health effects, so while BMI is an imperfect measure of healthy body weight, it is a useful indicator of whether any additional testing or action is required.

Category BMI range - kg/m2
Severe Thinness < 16
Moderate Thinness 16 - 17
Mild Thinness 17 - 18.5
Normal 18.5 - 25
Overweight 25 - 30
Obese Class I 30 - 35
Obese Class II 35 - 40
Obese Class III > 40

Risks associated with being overweight--

Being overweight increases the risk of a number of serious diseases and health conditions. Below is a list of said risks, according to the Centers for Disease Control and Prevention (CDC):

1 High blood pressure
2 Higher levels of LDL cholesterol, which is widely considered "bad
cholesterol," lower levels of HDL cholesterol, considered to be good
cholesterol in moderation, and high levels of triglycerides
3 Type II diabetes
4 Coronary heart disease
5 Stroke
6 Gallbladder disease
7 Osteoarthritis, a type of joint disease caused by the breakdown of joint cartilage
8 Sleep apnea and breathing problems
9 Certain cancers (endometrial, breast, colon, kidney, gallbladder, liver)
10 Low quality of life
11 Mental illnesses such as clinical depression, anxiety, and others
12 Body pains and difficulty with certain physical functions
13 Generally, an increased risk of mortality compared to those with a healthy
BMI

Risks associated with being underweight--

Being underweight has its own associated risks, listed below:

1 Malnutrition, vitamin deficiencies, anaemia (lowered ability to carry blood
vessels)
2 Osteoporosis, a disease that causes bone weakness, increasing the risk of
breaking a bone
3 A decrease in immune function
4 Growth and development issues, particularly in children and teenagers
5 Possible reproductive issues for women due to hormonal imbalances that
can disrupt the menstrual cycle. Underweight women also have a higher
chance of miscarriage in the first trimester
6 Potential complications as a result of surgery
7 Generally, an increased risk of mortality compared to those with a healthy
BMI

DISCLAIMER:
Kindly consider this calculator as guidance only. Visit a doctor for their assessment before taking any action.