JavaScript NaN Property

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# JavaScript NaN Property

Complete Number Object Reference

## Definition and Usage

The NaN property is a special value representing Not-a-Number. This property is used to indicate a value is not a number. A number object may be set to this value to indicate that it is not really a number.

Tip: Use the isNaN() global function to see if a value is an NaN value.

## Syntax

    Number.NaN

## Example

    <script type="text/javascript">

    var Month=30;

    if (Month < 1 || Month > 12)
    {
    Month = Number.NaN;
    }

    document.write(Month);

    </script>

The output of the code above will be:

    Nan

## Try-It-Yourself Demos

NaN
In this example we will use NaN to indicate a value is not a number.

Complete Number Object Reference

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