.JS File Extension

JavaScript File

Developer N/A
Popularity
4.0  |  303 Votes
 

What is a JS file?

A JS file is a plain text file that contains JavaScript code. It is used to execute JavaScript instructions in a webpage. JS files may include functions that open and close windows, validate form fields, enable rollover images, or create dropdown menus.

More Information

Screenshot of a .js file in Microsoft Visual Studio Code
JS file open in Microsoft Visual Studio Code

Web developers use JavaScript to add dynamic and interactive elements to webpages. One of the ways developers can add JavaScript functions to a webpage is by importing them using a JS file.

Developers usually import JS files in the <head> or <body> sections of a webpage's HTML, as shown below:

<head> <script type="text/javascript" src="FileInfo.comExample.js"></script> </head>

JS files often contain standard or site-wide functions that a developer wants to include on each of a site's webpages. Storing the functions in a single, importable JS file makes them easier to maintain and troubleshoot.

How to open a JS file

You can open and edit a JS file in any text or source code editor. Source code editors, such as Microsoft Visual Studio Code and GitHub Atom contain helpful syntax-highlighting and code-editing tools that make reading and editing JS files easier.

Open and view .JS files with File Viewer Plus.Free Download

Programs that open JS files

JScript Executable Script

Developer N/A
Popularity
3.7  |  89 Votes
 

Executable script written in JScript, Microsoft's version of JavaScript

Programs that open JS files

Windows
Windows-based script host (Wscript.exe)

Verified by FileInfo.com

The FileInfo.com team has independently researched all file formats and software programs listed on this page. Our goal is 100% accuracy and we only publish information about file types that we have verified.

If you would like to suggest any additions or updates to this page, please let us know.