Body Mass Index (BMI)


Your Minumum Proper Weight


Your Maximum Proper Weight

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BMI Body Mass Index

Body mass index (BMI) is a measure of body fat based on height and weight that applies to adult men and women. See below how BMI is interpreted for adults. For adults 20 years old and older, BMI is calculated with standard weight status categories below.

  • 18-25 Normal Weight
  • 25-30 Overweight
  • 30-40 Obesity
  • Above 40 Morbid Obesity

What is BMI and how is it used?

Body mass index (BMI) is a measure of body fat based on height and weight that applies to adult men and women. BMI is an inexpensive and easy-to-calculate screening tool for measuring body fat. It is not a diagnostic tool because it does not measure body fat directly, but it is correlated with other measures of body fat.

A person’s BMI can be calculated by using the following formula:

BMI = weight (in kg) / height2 (in m2).

normal weight = 18.5 – 24.9
overweight = 25 – 29.9
obesity = BMI of 30 or greater
extreme obesity = BMI of 40 or greater

Body mass index, or BMI, is most commonly used as a tool to screen for potential weight-related health problems. By calculating your BMI, you can get an estimate of whether you are at a healthy weight, underweight, overweight, or obese. This information can then help you and your healthcare provider make decisions about lifestyle changes or treatments that could improve your overall health. Additionally, research has shown that having a high BMI is linked to an increased risk of various diseases and conditions, including heart disease, stroke, type 2 diabetes, and certain types of cancer. Therefore, knowing your BMI can be an important first step in taking steps to protect your health.

What are other ways to assess excess body fatness besides BMI?

There are a few other ways to assess excess body fatness besides BMI. One is to measure your waist-to-hip ratio. To do this, measure the circumference of your waist and then divide that measurement by the circumference of your hips. A waist-to-hip ratio greater than 0.85 for women or greater than 1.0 for men indicates an increased risk for obesity-related health problems.

Another way to assess excess body fat is to measure your body fat percentage. This can be done using a variety of methods, such as skinfold thickness measurements, bioelectrical impedance analysis, or DEXA scans. However, these methods are not always accurate and should only be used as estimates.

How is BMI calculated manually?

Measurement UnitsFormula
Metric Kg & meters (or cm)

Metric BMI Formula: weight (kg) / [height (m)]2

Example: Weight = 80 kg, Height = 185 cm (1.85 m)
Calculation: 80 ÷ (1.85)2 = 23.37

Imperial (Pounds and inches)

Imperial BMI Formula: weight (lb) / [height (in)]2 x 703

Example: Weight = 160 lbs, Height = 5’10″ (70″)
Calculation: [160 ÷ (70)2] x 703 = 23