HTML <script> defer Attribute

The HTML defer attribute is a Boolean attribute that is used to specify that script is executed when the page has finished parsing. This attribute only works with external scripts.

Syntax:

<script defer>

Example:

HTML

<!DOCTYPE html>
<html>

<head>
    <title>
        HTML <script> defer Attribute
    </title>
</head>

<body style="text-align:center;">
    <h1 style="color:green"> 
        GeeksForGeeks 
    </h1>

    <h2> 
        HTML <script> defer Attribute
    </h2>

    <script id="myGeeks"
            type="text/javascript"
            src="my_script.js"
            defer>
    </script>
    <br>
    <button type="button"
            onclick="myFunction()">
      Submit
  </button>

</body>

</html>

External script: my_script.js

javascript

function myFunction() {
    alert("Script works");
}

Output: Before Click:

After Click:

Supported Browsers: The browsers supported by <script> defer Attribute are listed below:

Google Chrome
Edge 12 and above
Internet Explorer 10 and above
Firefox 3.5 and above
Apple Safari
Opera

HTML <script> defer Attribute

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