BMI Calculator

By Alan Frost, updated January, 2014

The BMI is a very common way to assess if your current body weight is ideal or if you are over or under weight. It is very easy to calculate, but unfortunately, it also often produces drastically poor results. The reason for this is that BMI does not take body composition into account. By body composition, I mean the percentage of your body that is fat and the percentage that is muscle. To give you an example, if a heavyweight bodybuilder with the world's lowest body fat percentage were to input his data into a BMI calculator, it would say he is morbidly obese.

Often, it also does not take your build into account either, producing even worse results. Our calculator does take this into account, so it should produce decent estimates for most people. However, treat the result as a rough estimate, and if you are particularly muscular or particularly weak, know that it will produce results that are off the mark.

In general, I would recommend that everyone instead uses a body fat percentage based assessment, and instead aims to reduce body fat to a normal range (e.g. 10-20% for men and 15-25% for women). You can learn more about this (and see some relevant images) in the article titled Body Fat Calculator.

BMI Calculator

Enter weight:
Enter height:
Your BMI is:

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