async attribute for external scripts

Last updated on : 2022-04-10

Note:
async attribute for external scripts shows a browser compatibility score of 93. This is a collective score out of 100 to represent browser support of a web technology. The higher this score is, the greater is the browser compatibility. The browser compatibility score is not a 100% reflection for every browser and the web technology support. However, it does give you an estimate on how much you should rely on a particular web technology in terms of browser compatibility.

Overview

The boolean async attribute on script elements allows the external JavaScript file to run when it's available, without delaying page load first.

Specifications

HTML Standard # the-script-element

Browser Compatibility

  • async attribute for external scripts on IE is fully supported on 10-11, partially supported on None of the versions, and not supported on 5.5-9 IE versions.
  • async attribute for external scripts on Edge is fully supported on 12-99, partially supported on None of the versions, and not supported on below 12 Edge versions.
  • async attribute for external scripts on Firefox is fully supported on 3.6-100, partially supported on None of the versions, and not supported on 2-3 Firefox versions.
  • async attribute for external scripts on Chrome is fully supported on 8-103, partially supported on None of the versions, and not supported on 4-7 Chrome versions.
  • async attribute for external scripts on Safari is fully supported on 5.1-15.4, partially supported on 5-5, and not supported on 3.2-4 Safari versions.
  • async attribute for external scripts on Opera is fully supported on 15-83, partially supported on None of the versions, and not supported on 9.5-12.1 Opera versions.
  • async attribute for external scripts on Safari on iOS is fully supported on 5-15.4, partially supported on None of the versions, and not supported on 3.2-4 Safari on iOS versions.
  • async attribute for external scripts on Android Browser is fully supported on 3-99, partially supported on None of the versions, and not supported on 2.3-2.1 Android Browser versions.
  • async attribute for external scripts on Opera Mobile is fully supported on 64-64, partially supported on None of the versions, and not supported on 10-12 Opera Mobile versions.
  • async attribute for external scripts on Chrome for Android is fully supported on 97-100, partially supported on None of the versions, and not supported on below 97 Chrome for Android versions.
  • async attribute for external scripts on Firefox for Android is fully supported on 95-98, partially supported on None of the versions, and not supported on below 95 Firefox for Android versions.
  • async attribute for external scripts on Samsung Internet is fully supported on 4-16, partially supported on None of the versions, and not supported on below 4 Samsung Internet versions.
93
Hightooltip

Browser Compatibility Score

Chrome IE
Medium

Browser Support For IE Versions

10-11
Fully
-
Partially
5.5-9
No Support
Chrome Edge
High

Browser Support For Edge Versions

12-99
Fully
-
Partially
-
No Support
Chrome Firefox
High

Browser Support For Firefox Versions

3.6-100
Fully
-
Partially
2-3
No Support
Chrome Chrome
High

Browser Support For Chrome Versions

8-103
Fully
-
Partially
4-7
No Support
Chrome Safari
High

Browser Support For Safari Versions

5.1-15.4
Fully
5-5
Partially
3.2-4
No Support
Chrome Opera
High

Browser Support For Opera Versions

15-83
Fully
-
Partially
9.5-12.1
No Support
Chrome Safari on iOS
High

Browser Support For Safari on iOS Versions

5-15.4
Fully
-
Partially
3.2-4
No Support
Chrome Android Browser
High

Browser Support For Android Browser Versions

3-99
Fully
-
Partially
2.3-2.1
No Support
Chrome Opera Mobile
Medium

Browser Support For Opera Mobile Versions

64-64
Fully
-
Partially
10-12
No Support
Chrome Chrome for Android
High

Browser Support For Chrome for Android Versions

97-100
Fully
-
Partially
-
No Support
Chrome Firefox for Android
High

Browser Support For Firefox for Android Versions

95-98
Fully
-
Partially
-
No Support
Chrome Samsung Internet
High

Browser Support For Samsung Internet Versions

4-16
Fully
-
Partially
-
No Support

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Last Modified date

2022-04-10

Browser Support for async attribute for external scripts

  • ChromeChrome
  • Safari Safari
  • Firefox Firefox
  • IE Internet Explorer
  • Opera Opera
  • Edge Edge

References


Data sourced from

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Sarah

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