Using the Body Mass Index (BMI) Calculator, the BMI value and accompanying weight status may be determined while taking age into account. Use the "Other Units" tab to change units into either US or metric units, or the "Metric Units" tab for the International System of Units. Notably, the calculator also determines the Ponderal Index in addition to BMI; these are covered in more detail below. Introduction to BMI Based on height and weight, the BMI calculates a person's leanness or corpulence and attempts to quantify tissue mass. It is frequently used as a broad indicator of a person's body weight in relation to their height. According on the range the value falls within, a person is classified as being underweight, normal weight, overweight, or obese based on the value received from the BMI calculation. These BMI ranges are sometimes further broken down into subgroups like severely underweight or very severely obese, depending on variables like geography and age. The health repercussions of being overweight or underweight can be profound. Therefore, even though BMI is a flawed estimate of a healthy body weight, it can be used to determine whether further testing or intervention is necessary. The many BMI-based categories that the calculator uses are shown in the table below. Table of adult BMI Based on BMI readings, this is the recommended body weight for adults by the World Health Organization (WHO). Both men and women who are at least 20 years old can utilize it. 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 For adults, a BMI chart This graph of BMI categories is based on information from the World Health Organization. Subdivisions of a broad category are represented by the dashed lines. BMI chart for kids and teens, ages 2 to 20 The BMI classification is advised for kids and teenagers between the ages of 2 and 20, according to the Centers for Disease Control and Prevention (CDC). Category Percentile Range Underweight <5% Healthy weight 5% - 85% At risk of overweight 85% - 95% Overweight >95% BMI graph for kids and teens, ages 2 to 20 Growth charts based on BMI-for-age percentiles from the Centers for Disease Control and Prevention (CDC). Graph for boys Graph for girls the dangers of being overweight The risk of several significant diseases and health issues rises with weight gain. According to the Centers for Disease Control and Prevention (CDC), the following risks are listed: elevated blood pressure Higher levels of the generally regarded "bad cholesterol," LDL, lower levels of the generally regarded "good cholesterol," HDL, and higher levels of triglycerides Diabetes Type II cardiovascular disease Stroke a gallbladder condition Joint disease known as osteoarthritis, which is brought on by the destruction of joint cartilage, issues with breathing and sleep apnea specific cancers (endometrial, breast, colon, kidney, gallbladder, liver) poor standard of living clinical depression, anxiety, and other mental diseases body aches and trouble performing some physical tasks Generally speaking, a higher mortality risk in comparison to people with a healthy BMI The list above demonstrates the wide range of detrimental, and occasionally fatal, effects that being overweight may have. Ideally, a person should see their doctor to decide whether or not they need to make any adjustments to their lifestyle in order to be healthier. In general, a person should attempt to maintain a BMI below 25 kg/m2. the dangers of being underweight There are hazards linked with being underweight, which are described below: vitamin deficiency, anemia, and poor nutrition (lowered ability to carry blood vessels) Osteoporosis is a condition that weakens bones and raises the chance of fracturing a bone. a decline in immunological response difficulties with growth and development, particularly in kids and teenagers hormonal imbalances that may affect a woman's ability to conceive since they can interfere with her menstrual cycle. Additionally, the likelihood of miscarriage in the first trimester is increased among underweight women. Surgery-related problems that could occur Generally speaking, a higher mortality risk in comparison to people with a healthy BMI Being underweight is occasionally a symptom of an illness or underlying condition, such as anorexia nervosa, which carries hazards of its own. If you believe you or someone you know is underweight, go to your doctor right once, especially if the cause does not seem clear. BMI's limitations BMI has its limitations even though it is a popular and helpful indication of a healthy body weight. BMI is simply a rough measure and cannot account for body composition. Because there are many different body types and variations in muscle, bone, and fat distribution, BMI should be used in conjunction with other measurements rather than as the only way to establish a person's healthy body weight. in grownups: Because BMI measures extra body weight rather than excess body fat, it cannot be completely correct. Additional variables that affect BMI include age, sex, ethnicity, muscle mass, body fat, and amount of activity. For instance, an elderly person with a healthy weight who is fully sedentary in daily life may have a lot of excess body fat despite not being overweight. In contrast, a younger individual with a higher muscle composition and the same BMI would be seen as healthy. It is entirely feasible that sportsmen, especially bodybuilders who would be labeled overweight because muscle weighs more than fat, are actually at a healthy weight for their sport. With the same BMI, older persons typically have more body fat than younger adults. For an equivalent BMI, women often have more body fat than men do. Due to their great muscle mass, athletes and those who are muscular may have BMIs that are higher. Among kids and teenagers: Children and adolescents can also be affected by the same variables that restrict the effectiveness of BMI in adults. Height and the degree of sexual development can also affect children's BMI and body fat. For obese children, BMI is a stronger indication of extra body fat than. In contrast to overweight children, whose BMI may be caused by higher levels of either fat or fat-free mass, obese children's BMI is a better predictor of excess body fat than it is for overweight children (all body components except for fat, which includes water, organs, muscle, etc.). The variation in BMI in skinny children may also be caused by their body fat-free mass. Nevertheless, for 90–95 percent of the population, BMI is a reliable indicator of body fat and can be used in combination with other metrics to assist identify a person's healthy body weight. BMI calculator The formulas for determining BMI using the International System of Units (SI) and the US Customary System (USC), using a 5'10" and 160-pound person as an example, are listed below: Index Ponderal In that it gauges a person's leanness or corpulence depending on their height and weight, the Ponderal Index (PI) is comparable to the BMI. The key distinction between the PI and BMI is that the height in the formula is squared rather than rounded in the former (provided below). BMI is a valuable tool when analyzing huge populations, but it cannot accurately assess an individual's leanness or corpulence. While both the PI and BMI have comparable limitations, the PI is more accurate when used with very tall or very short people, while the BMI tends to reflect unusually high or low levels of body fat for people at the extreme ends of the height and weight continuum. The equation for calculating a person's PI using USC is shown below, using a 5'10" 160-pound person as an example.

Using the Body Mass Index (BMI) Calculator, the BMI value and accompanying weight status may be determined while taking age into account. Use the “Other Units” tab to change units into either US or metric units, or the “Metric Units” tab for the International System of Units. Notably, the calculator also determines the Ponderal Index in addition to BMI; these are covered in more detail below.

Introduction to BMI
Based on height and weight, the BMI calculates a person’s leanness or corpulence and attempts to quantify tissue mass. It is frequently used as a broad indicator of a person’s body weight in relation to their height. According on the range the value falls within, a person is classified as being underweight, normal weight, overweight, or obese based on the value received from the BMI calculation. These BMI ranges are sometimes further broken down into subgroups like severely underweight or very severely obese, depending on variables like geography and age. The health repercussions of being overweight or underweight can be profound.

Therefore, even though BMI is a flawed estimate of a healthy body weight, it can be used to determine whether further testing or intervention is necessary. The many BMI-based categories that the calculator uses are shown in the table below.

Table of adult BMI

Based on BMI readings, this is the recommended body weight for adults by the World Health Organization (WHO). Both men and women who are at least 20 years old can utilize it.

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

For adults, a BMI chart
This graph of BMI categories is based on information from the World Health Organization. Subdivisions of a broad category are represented by the dashed lines.

BMI chart for kids and teens, ages 2 to 20
The BMI classification is advised for kids and teenagers between the ages of 2 and 20, according to the Centers for Disease Control and Prevention (CDC).

Category Percentile Range
Underweight <5%
Healthy weight 5% – 85%
At risk of overweight 85% – 95%
Overweight >95%

BMI graph for kids and teens, ages 2 to 20
Growth charts based on BMI-for-age percentiles from the Centers for Disease Control and Prevention (CDC).

Graph for boys
Graph for girls

the dangers of being overweight
The risk of several significant diseases and health issues rises with weight gain. According to the Centers for Disease Control and Prevention (CDC), the following risks are listed:

• elevated blood pressure
• Higher levels of the generally regarded “bad cholesterol,” LDL, lower levels of the generally regarded “good cholesterol,” HDL, and higher levels of triglycerides
• Diabetes Type II
  cardiovascular disease
• Stroke
  a gallbladder condition
• Joint disease known as osteoarthritis, which is brought on by the destruction of joint
  cartilage
• issues with breathing and sleep apnea
• specific cancers (endometrial, breast, colon, kidney, gallbladder, liver)
  poor standard of living
• clinical depression, anxiety, and other mental diseases
• body aches and trouble performing some physical tasks

Generally speaking, a higher mortality risk in comparison to people with a healthy BMI
The list above demonstrates the wide range of detrimental, and occasionally fatal, effects that being overweight may have. Ideally, a person should see their doctor to decide whether or not they need to make any adjustments to their lifestyle in order to be healthier. In general, a person should attempt to maintain a BMI below 25 kg/m2.

the dangers of being underweight
There are hazards linked with being underweight, which are described below:

vitamin deficiency, anemia, and poor nutrition (lowered ability to carry blood vessels)
Osteoporosis is a condition that weakens bones and raises the chance of fracturing a bone.
a decline in immunological response
difficulties with growth and development, particularly in kids and teenagers
hormonal imbalances that may affect a woman’s ability to conceive since they can
interfere with her menstrual cycle. Additionally, the likelihood of miscarriage in the first trimester is increased among underweight women.
Surgery-related problems that could occur
Generally speaking, a higher mortality risk in comparison to people with a healthy BMI

Being underweight is occasionally a symptom of an illness or underlying condition, such as anorexia nervosa, which carries hazards of its own. If you believe you or someone you know is underweight, go to your doctor right once, especially if the cause does not seem clear.

BMI’s limitations
BMI has its limitations even though it is a popular and helpful indication of a healthy body weight. BMI is simply a rough measure and cannot account for body composition. Because there are many different body types and variations in muscle, bone, and fat distribution, BMI should be used in conjunction with other measurements rather than as the only way to establish a person’s healthy body weight.

in grownups:

Because BMI measures extra body weight rather than excess body fat, it cannot be completely correct. Additional variables that affect BMI include age, sex, ethnicity, muscle mass, body fat, and amount of activity. For instance, an elderly person with a healthy weight who is fully sedentary in daily life may have a lot of excess body fat despite not being overweight. In contrast, a younger individual with a higher muscle composition and the same BMI would be seen as healthy. It is entirely feasible that sportsmen, especially bodybuilders who would be labeled overweight because muscle weighs more than fat, are actually at a healthy weight for their sport.

With the same BMI, older persons typically have more body fat than younger adults.
For an equivalent BMI, women often have more body fat than men do.
Due to their great muscle mass, athletes and those who are muscular may have BMIs that are higher.

Among kids and teenagers:

Children and adolescents can also be affected by the same variables that restrict the effectiveness of BMI in adults. Height and the degree of sexual development can also affect children’s BMI and body fat. For obese children, BMI is a stronger indication of extra body fat than.

In contrast to overweight children, whose BMI may be caused by higher levels of either fat or fat-free mass, obese children’s BMI is a better predictor of excess body fat than it is for overweight children (all body components except for fat, which includes water, organs, muscle, etc.). The variation in BMI in skinny children may also be caused by their body fat-free mass.

Nevertheless, for 90–95 percent of the population, BMI is a reliable indicator of body fat and can be used in combination with other metrics to assist identify a person’s healthy body weight.

BMI calculator
The formulas for determining BMI using the International System of Units (SI) and the US Customary System (USC), using a 5’10” and 160-pound person as an example, are listed below:

Index Ponderal
In that it gauges a person’s leanness or corpulence depending on their height and weight, the Ponderal Index (PI) is comparable to the BMI. The key distinction between the PI and BMI is that the height in the formula is squared rather than rounded in the former (provided below). BMI is a valuable tool when analyzing huge populations, but it cannot accurately assess an individual’s leanness or corpulence. While both the PI and BMI have comparable limitations, the PI is more accurate when used with very tall or very short people, while the BMI tends to reflect unusually high or low levels of body fat for people at the extreme ends of the height and weight continuum.

The equation for calculating a person’s PI using USC is shown below, using a 5’10” 160-pound person as an example.