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JavaScript NaN Property
JavaScript Global Functions
Definition and Usage
The NaN property represents "Not-a-Number" value. This property indicates that a value is not a legal number.
Tip: Use the isNaN() global function to see if a value is a NaN value.
Syntax
Number.NaN
Browser Support
The NaN property is supported in all major browsers.
Example
Example
Here, the variable "Month" is assigned NaN if it is smaller than 1, or greater than 12:
<script type="text/javascript">
var Month=13;
if (Month < 1 || Month > 12)
{
Month = Number.NaN;
}
document.write(Month);
</script>
var Month=13;
if (Month < 1 || Month > 12)
{
Month = Number.NaN;
}
document.write(Month);
</script>
The output of the code above will be:
NaN
Try it yourself »
JavaScript Global Functions
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Tutorials, references, and examples are constantly reviewed to avoid errors, but we cannot warrant full correctness of all content.
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Copyright 1999-2012 by Refsnes Data. All Rights Reserved.
Tutorials, references, and examples are constantly reviewed to avoid errors, but we cannot warrant full correctness of all content.
While using this site, you agree to have read and accepted our terms of use and privacy policy.
Copyright 1999-2012 by Refsnes Data. All Rights Reserved.