This is a very small example of what you can do with Javascript. A more complex example is the shopping trolley
Your Body Mass Index (BMI) is a widely recognised means of determining whether your weight is within healthy limits for your height. It is calculated from the following formula:
or, in English, your weight (in kilogrammes) divided by the square of your height (in metres). To calculate your Body Mass Index enter your height and weight, then press the calculate button.


Metric  Imperial  

Kg m 
st lb ft in 



A BMI of 18.525 is considered to be the normal range (= good). Lower than 18.5 indicates that you're underweight. 2530
is overweight and over 30 is obese. 