Free Online Calculators

Body Mass Index Calculator


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Free Online Body Mass Index Calculator: This calculator computes the body mass index and rates it appropriately for men, women.

The body mass index:

The body mass index (BMI) is a quantity that can be used to estimate a person's body size. BMI is defined as the weight divided by the square of the height, expressed in kg / m2. The calculation of the body mass index makes it possible to quantify excess weight or underweight. It also indicates the appropriate weight to optimal health. A healthy weight is a reflection of a healthy diet!


BMI = WEIGHT (KG) / height²(M)


BMI (kg / m2) Interpretation (according to WHO)
Below 16 Anorexia or undernutrition
Between 16.5 and 18.5 Leanness
Between 18.5 and 25 normal body
Between 25 and 30 Overweight
Between 30 and 35 Moderate Obesity (Class 1)
Between 35 and 40 High Obesity (Class 2)
Greater than 40 Morbid or massive obesity

BMI Chart for Adults:

This is a graph of BMI categories based on the World Health Organization data

BMI Chart pdf

Advantages of BMI:

BMI is generally considered the best way to determine if a person is at a healthy weight. Using BMI is popular because it is simple, fast, effective and applies to adult men and women aged 18 to 65. BMI is a useful tool for quickly assessing weight classification. Although it does not directly measure body fat, it is more accurate to approximate the degree of body fat than weight alone. In addition, you must not be of an exact weight or measurement, to be considered "normal". There is a range within each classification to allow different body types and shapes. For example, you can be 10 to 15 pounds more than the same height counterpart and still fall into a normal weight range.

Disadvantages of BMI:

BMI has its limits. Because it is not a measure of body fatness, very muscular people often fall into the overweight category when they are not too fat. In addition, BMI can place people who have lost muscle in the healthy weight category. Measuring BMI for very short people or pregnant women are not appropriate. It is believed that excessive abdominal fat is more dangerous to health than hip or thigh fat. A woman with a waist circumference greater than 35 inches and a man with a waist circumference greater than 40 inches may be at an increased risk of developing high blood pressure, stroke and heart disease. As a result, the National Institute of Health (NIH) has asked physicians to measure patients' waistlines.

Ponderal Index:

Also known as Corpulence Index , is a measure of body weight in relation to the body size, similar to the body mass index. While it can apply to people of any age, it is typically used in pediatrics to assess the ratio of height to weight of a person. The main difference between the PI and BMI is the cubing rather than squaring of the height in the formula.

Ponderal Index formula:

PI=WEIGHT (KG) / height ³ (M)

the Ponderal Index is not widely used.