Whether you’ve made the decision to try and improve your overall health or you just want to know if you’re a healthy weight, learning how to calculate your body mass index is a good place to start.

The BMI (Body Mass Index) is used by health professionals around the world and is the preferred method for checking whether you're within a healthy weight range for your height.

 There are several methods available for working out your BMI, so just choose whichever you prefer.


How to Figure Your BMI Manually



This is a straightforward process and just involves a couple of personal measurements - your height and your weight. You can work out your BMI using either metric or imperial measures.

Imperial Calculation: BMI = (weight in pounds x 703) / (height in inches (squared));
Metric Calculation: BMI = (weight in kilograms) / (height in meters (squared)).

For example, using the metric formula, someone weighing 55 kilos with a height of 1.65m would make the calculation as follows:


Therefore, this person has a BMI of 20.2 and within the normal range.

BMI Categories

Underweight (below 18.5),
Normal (18.5-24.9),
Overweight (25-29.9),
Obese (30+).

Other Methods for Calculating Your BMI

Body Fat Monitors

Body fat monitors provide a more accurate BMI reading since they take into account your muscle mass. You can either purchase one to use in the privacy of your own home or alternatively, many gyms have body fat monitors for the use of their members.



Online

Searching for BMI Calculators; using an online search engine returns hundreds of results. These are very user friendly and generally involve inputting your height, weight and sometimes your age and gender. As well providing as your BMI figure, you may be given further advice relating to your result.

This one from the National Heart, Lung, and Blood Institute is an easy straightforward calculator to use online Calculator. It has the option of metric and imperial.

Your Doctor

Don't forget your GP who can be a valuable source of information. Along with calculating your BMI, you may be given further health checks or offered helpful information for improving your diet and lifestyle.

Who Shouldn't Use The BMI?

The BMI figure isn't an accurate guide for everyone. For instance, athletes who are very lean or muscular can produce misleading or skewed results. This is because their body mass is often made up of more muscle than the rest of us.

Likewise, pregnant ladies, the sick or elderly can all produce an unreliable BMI figure. Children have a separate method for checking their BMI which takes into account their weight, height and age. They're then categorized into percentiles measured against other children.

Remember, your body mass index is just one indicator of your health. Keeping your BMI within the normal range combined with eating a balanced diet and taking regular exercise, all contribute towards living a longer, healthier life.