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Window alert() Method

❮ Window Object

Example

Display an alert box:

alert("Hello! I am an alert box!!");
Try it Yourself »

More "Try it Yourself" examples below.


Definition and Usage

The alert() method displays an alert box with a specified message and an OK button.

An alert box is often used if you want to make sure information comes through to the user.

Note: The alert box takes the focus away from the current window, and forces the browser to read the message. Do not overuse this method, as it prevents the user from accessing other parts of the page until the box is closed.


Browser Support

Method
alert() Yes Yes Yes Yes Yes

Syntax

alert(message)

Parameter Values

Parameter Type Description
message String Optional. Specifies the text to display in the alert box, or an object converted into a string and displayed


Technical Details

Return Value: No return value

More Examples

Example

Alert box with line-breaks:

alert("Hello\nHow are you?");
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Example

Alert the hostname of the current URL:

alert(location.hostname);
Try it Yourself »

Related Pages

Window Object: confirm() Method

Window Object: prompt() Method


❮ Window Object