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Source Code

.js — JavaScript Source Code

Source code written in JavaScript, the programming language of the web. Runs in browsers natively and, via Node.js, on servers and the command line too.

Also known as: .mjs, .cjs

Commonly opened with
  • Any web browser
  • Node.js
  • Visual Studio Code
Supported platforms
  • Windows
  • macOS
  • Linux
  • Web / Cross-platform
  • Android
  • iOS
Editable?
Yes, with common software
Viewable without special tools?
Usually, yes
Commonly converted to
  • .min.js
Inherent format risk
Use some caution
Safety guidance (not a guarantee)

Scripts can run commands on your computer when executed. Only run scripts from sources you trust, and review the contents in a text editor first if you're unsure.

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Frequently asked questions

What is a .js file?

Source code written in JavaScript, the programming language of the web. Runs in browsers natively and, via Node.js, on servers and the command line too.

Can I edit a .js file?

Yes — .js files are commonly editable with software such as Any web browser.

Does having a .js extension mean the file is safe?

No single extension can guarantee that. Scripts can run commands on your computer when executed. Only run scripts from sources you trust, and review the contents in a text editor first if you're unsure. Always consider where the file came from, not just its name.

Privacy: The lookup above runs entirely in your browser. Nothing you type is uploaded, logged, or sent anywhere.

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