A Answers (5)

Mehmet Oz, MD, Cardiology, answeredTo determine your body mass index you must know your weight and your height. Watch this video demonstration of a BMI calculation.
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The formula for BMI is in metric units: kilograms per metersquared. If you don’t want to convert your height and weight to metric, there are multiple calculators on the web to use (search for “BMI calculator), or you can use the following nonmetric formula: 704 times (X) pounds of body weight, divided by height in inchessquared.
The same formula is used for adult men and women of any age, but children are graphed on a different chart, and BMI is expressed as a percentile for that age or height.
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Honor Society of Nursing (STTI) answered
The body mass index (BMI) is a ratio of your height and weight. To calculate your BMI, use this formula:
weight (lb) / [height (in)]2 x 703
Calculate BMI by dividing weight in pounds (lbs) by height in inches (in) squared and multiplying by a conversion factor of 703.
Example: Weight = 150 lbs, Height = 5'5" (65")
Calculation: [150 ÷ (65)2] x 703 = 24.96
If your BMI is between 25 and 30, you are considered overweight; if it is above 30, you are considered obese. For instance, if you are 5’ 5” tall and weigh 151 pounds, you are considered to be “overweight.” If you are the 5’ 5” tall and weigh 180 pounds, you are in the “obese” category. If you are 5’ 11”, you are overweight at 179 pounds and obese at 215 pounds. Again, being overweight or obese is associated with a risk of chronic illness such as cardiovascular disease, hypertension, and type 2 diabetes.
It’s important to keep in mind that while the BMI is used by many healthcare practitioners, it can be misleading in some adults. Some men and women may be given a higher BMI yet have large frames or an abundance of muscle. Even though these men and women may have a BMI over 25, they may not have excessive body fat.Helpful? 5 people found this helpful. 
Alberto Gamboa , NASM Elite Trainer, Fitness, answered
Ideal Weight Calculator (Body Mass Index) is a reliable indicator of your body’s fitness level, and most importantly, your health risk. It works by calculating your weight and height.
To use a calculator to deturmine your BMI, go to:
http://www.weightlossplans4you.com/idealweightcalculator.html
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National Academy of Sports Medicine answeredTo figure out your BMI it will require a little math. I use charts and graphs with my live clients so it is faster and easier to gauge where someone is.
BMI = ( Weight in Pounds / ( Height in inches x Height in inches ) ) x 703
Or your BMI will be figured out for you when you go through Dr. Oz's 11 Weeks to Move it and Lose it in 2011. Just visit http://www.doctoroz.com/videos/moveitandloseit2011 to get started today!
A healthy Body Mass Index (BMI) reading is 18.524.9. The official scores are as follows;
Below 18.5 = Underweight18.5 – 24.9 = Normal
25.0 – 29.9 = Overweight
30.0  39.9 = Obese
40 and above = Morbidly obese
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