I'm not a javascript programmer, but I have to use it for a calculation I need to do on a wordpress page. 

Here is what I need:

* 3 fields in html where I can enter a number (a form).
* a text field where the multiplication is "printed"
* if I change one element, a new result must apear, without me needing to push any button.

any idea on how to do this? 
I know how to do the calculation as such, but not that it works automatically. 

HEre is what I got so far:

```
    <html>

<head>

<title>Simple Javascript Calculator - Basic Arithmetic Operations</title>

<script language="javascript" type="text/javascript">
function multiply(){
    a=Number(document.calculator.number1.value);
    b=Number(document.calculator.number2.value);
    c=a*b;
    document.calculator.total.value=c;
}
</script>

</head>

<body>

<!-- Opening a HTML Form. --> 
<form name="calculator">

<!-- Here user will enter 1st number. --> 
Number 1: <input type="text" name="number1"> 

<!-- Here user will enter 2nd number. --> 
Number 2: <input type="text" name="number2"> 

<!-- Here result will be displayed. --> 
Get Result: <input type="text" name="total"> 

<!-- Here respective button when clicked, calls only respective artimetic function. --> 
<<input type="button" value="MUL" onclick="javascript:multiply();">

</form>

</body>
</html>

```

thanks