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JavaScript Number() Function

Complete Function Reference

Definition and Usage

The Number() function converts the value of an object to a number.

Syntax

Number(object)

Parameter	Description
object	Required. A JavaScript object

Tips and Notes

Note: If the parameter is a Date object, the Number() function returns the number of milliseconds since midnight January 1, 1970 UTC.

Note: If the object's value cannot be converted to a number, the Number() function returns NaN.

Example

In this example we will try to convert different objects to numbers:

<script type="text/javascript">

var test1= new Boolean(true);
var test2= new Boolean(false);
var test3= new Date();
var test4= new String("999");
var test5= new String("999 888");

document.write(Number(test1)+ "<br />");
document.write(Number(test2)+ "<br />");
document.write(Number(test3)+ "<br />");
document.write(Number(test4)+ "<br />");
document.write(Number(test5)+ "<br />");

</script>

The output of the code above will be:

Try-It-Yourself Demos

Number()
How to use Number().

Complete Function Reference

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