Skip to content
Related Articles

Related Articles

HTML | DOM Script async Property

View Discussion
Improve Article
Save Article
  • Last Updated : 25 Feb, 2022

The DOM Script async property is used to set or returns whether a script should be executed asynchronously or not. This property is used to reflect the async attribute. This attribute only works for the external script.

There are the following ways that the external script could be executed:

  • The script will be executed asynchronously with the rest of the page when async is present. Means while the page continues the parsing that time script will be executed.
  • If the defer is present but async is not present then the script will be executed when the page has finished parsing.
  • If both, async or defer is not present then the script is fetched and will execute immediately, even before the browser continues parsing the page.


  • It return the async property.
  • It is used to Set the async property.
    scriptObject.async = true|false

Property Values: It contains a Boolean value which specify that whether the script should be executed asynchronously as soon as it is available, or not.

  • True: It specifies that the script should be executed asynchronously.
  • false: It specifies that the script will not be executed asynchronously. By default, it is set to false.
    • Return Value: It returns a Boolean value which specifies that the script should be executed asynchronously or not.


      <!DOCTYPE html>
              HTML DOM Script async Property
      <body style="text-align:center;">
          <h1 style="color:green;">
          <h2>DOM Script async Property </h2>
          <p id="p1">Hello World!</p>
          <script id="myScript" src="demo_async.js" async></script>
          <!-- Button that trigger the Function -->
          <button onclick="myFunction()">Click me!</button>
          <p id="demo"></p>
          <!-- Main Function -->
              function myFunction() {
                  var x = document.getElementById("myScript").async;
                  document.getElementById("demo").innerHTML = x;


      • Before Clicking on Button:
      • After Clicking on Button:

      Supported Browsers: The browser supported by HTML DOM Script async property are listed below:

      • Google Chrome
      • Internet Explorer 10.0
      • Firefox
      • Safari
      • Opera

      My Personal Notes arrow_drop_up
Recommended Articles
Page :

Start Your Coding Journey Now!