BMI Calculator

Use our free BMI calculator to discover if your BMI (Body Mass Index) is ideal for your weight and height. Don’t forget to introduce exercise into your plan to start enjoying a wonderful new healthier lifestyle.

To calculate your BMI, simply drag the sliders on the BMI calculator to select your height and feet in inches or metres and your weight in either stones and pounds or kilograms.

What is my Body Mass Index?

The Body Mass Index calculation applies to both adult men and women, it does not apply to children. Your BMI may not be accurate if you're over the age of 60. This is because your bones may begin to weigh less as you get older. When you work out your BMI, remember to take into account your body frame and your build. For example, your BMI may not be accurate if you're a weight-trainer, an athlete.

Body Mass Index (BMI) is a measure of body mass based on height and weight, and can be a better measure than weight alone.

How it is calculated


Body mass index, BMI, is a number generated by dividing your weight in kilograms by your height in meters squared.

Body mass index (BMI) = weight(kg) / height(m)2

The resulting number gives an indication of your weight in relation to your height and if this is within healthy proportions or not. The following categories are used and are the same for men and women.

BMI (kg/m2) Category 
Below 18.5 Underweight
18.5 to 24.9 Healthy weight
25.0 to 29.9 Overweight
30 to 39.9 Obese
40 and above Morbidly obese (morbidly obese means that the amount you're overweight is harmful to your health)

When you know which plan's right for you then create your own

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