# How To Calculate BMI

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## How To Calculate BMI

Your body mass index (BMI) number is an important part to healthy living. Many obesity-related diseases can be avoided by having a normal BMI. But how do you calculate your BMI number? And what is the ideal BMI number to have?

### Step 1: Understanding BMI

The Body Mass Index number (BMI) is determined by a standard equation. This number is what doctors use to determine what percentage of your body is fat. Combining this number with additional risk factors, doctors can assess the risk for developing obesity-related diseases such as high blood pressure, high cholesterol, heart disease and diabetes.

### Step 2: Do The Math

There are two ways to calculate your BMI. In the U.S., divide your weight (in pounds) by your height (in inches), squared. Then multiply that number by 703. For metric users, simply divide your weight (in kilograms) by your height (in meters), squared. The resulting number is your BMI.

### Step 3: Normal Or Not?

The BMI number places us into four categories:
Underweight: Below 18.5
Normal Weight: 18.5 - 24.9
Overweight: 25.0 - 29.9
Obese: Above 30.0
The higher your BMI, the higher the risk of high blood pressure, high cholesterol, heart disease and diabetes.

### Step 4: Find Your Own

A man weighing 200 pounds and measuring 5'11" will yield a BMI of 27.9, which is in the overweight category. However, large amounts of muscle mass may skew the number as muscle is heavier than fat. The BMI number may overestimate body fat in athletes and underestimate body fat in older persons.