The above formula shows the method for calculating the Body Mass Index (or BMI for short).
The BMI is a very good indicator (for adults) in determining the total body fat content. However, it is by no means infallible. For example, an extremely muscular person might have their BMI in the overweight or even the obese range, yet that person could have a very low amount of body fat.
The numbers below show the BMI categories.

BMI below 18.5 – Underweight
BMI from 18.5 – 24.9 Normal Weight
BMI from 25 – 29.9 Overweight
BMI from 30 – 34.9 Obese
BMI from 35 – 38.9 Very Obese
BMI 39 and above Morbidly Obese

Please do not use the BMI formula or
this calculator as a basis for drastic
changes in your diet.
Always consult your doctor first.

Even though the formula defines the BMI in terms of kilograms and meters, this calculator will also accept entries in stones, pounds, grams, feet and inches. Yes, stones (1 stone = 14 pounds) are still in common usage in the British Isles and that’s the reason for including that unit of measurement.
You can input more than one number per line.
For example, if you are 63 inches tall, you could enter this value in the “inches” box OR you could input 5 feet then 3 inches in their respective boxes OR you could just enter 5.25 feet.

The same is true for the weight input boxes.
If you weigh 147 pounds you could just enter this in the “pounds” box OR you could enter 10.5 “stones”OR you could enter 10 “stones” and 7 “pounds”. (attn: Citizens of Britain & India – this might be the only online BMI Calculator that accepts “stones” and pounds for input).