BMI Calculator - Work Out Your Body Mass Index (Quetelet Index)
The founder of the Body Mass Index is Quetelet.
He worked out that there was a reasonably useful relationship between weight and lenght of your body.
Note, that I'd like to add a little extra info to the Body Mass Index.
More than is usually provided. So please continue to read on after you have tried the calculator.
I am also adding some useful links that show you how running can help when you want to reduce your BMI.

So now that you know your BMI... what is a high and what is a low BMI?
Normally the following general figures are used :
BMI < 20 :: |
Underweight |
BMI < 25 :: |
Normal weight |
BMI > 25 :: |
Overweight |
BMI > 30 :: |
Obese |

And so, also, for the risk people run to get heart and/or artery diseases.
Insurance companies use the BMI for example.
Is it a good indicator of cardiovascular problems?
First read these comments to the Body Mass Index and then judge for yourself:
BMI is dependent on both length and weight. The weight of children grows faster than their length. BMI is therefore not so useful for children.

When you are older the opposite happens: older people keep the same weight, but they decrease in length. So for elderly, the BMI is not that useful too.
Extremely tall people can't really use the BMI as well. For them weight divided by length to the third degree would be a more useful criterium.
Big people with lots of muscles (bodybuilders, big bad basketballplayers / footballplayers) can't use the Body Mass Index either. Muscles have a higher relative weight than fat.
Asian people generally have lower body fat. A BMI higher than 20 can already be a serious indicator of being overweight for an Asian person.
So using BMI as an indicator of obesity is not so useful for quite a few people. More than half of the world's population actually... :)
So, when you are in one of the above groups, then be a bit careful when interpreting the results.
However, if you are not extremely small or tall, don't have a body-builder body, then you are going to be fine with using the BMI calculator as a gauge for obesity.
Your score is over 25?
Well, if you are in one of the above groups, you may not have much to worry about. Check for other vital signs as well.
You probably know already whether or not you need to improve upon your situation. You may want to check out some of the links below to work out some ways to improve your BMI-reading and your health and fitness:
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Score lower than 25?
Good for you, but sorry, look at your belly, your exercise pattern and your eating habits first, before you decide you are healthy! And again, especially when you are Asian, a BMI-reading lower than 25 may still be bad news.
Use BMI as a useful indicator. Don't try to "explain away" a high BMI-reading by assuming you are okay and must be big-boned, big-muscled or whatever it is.
Use the time reading this page to work out if you can improve your health and fitness!

Want to improve your BMI?
Diet is a major factor!
Some governments are starting to move away from using BMI as the measure of health. Instead they usually include a few measures like waist-to-hip ratio and waist measurement.
I imagine that going forward these types of measures will become more and more important and that BMI will lose more of its importance.
Have you worked out you are overweight? Then why not set yourself a goal right now! Work out how much weight you need to lose to get in the healthy range (BMI < 25). And then...? Use the links above or below to start off your weight-loss and running journey!
Home > Running for Weight Loss > BMI Index Calculator
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