Editors & Viewers

JavaScript Viewer

View and edit JavaScript with highlighting — instantly and privately, right in your browser.

Loading JavaScript Viewer…

How it works

How to use the JavaScript Viewer

  1. Write or open code

    Type, paste, drop a file or press Sample. Syntax highlighting, bracket matching and search (Ctrl F) are built in.

  2. Edit comfortably

    Line numbers, code folding, multiple cursors and undo history work like a desktop editor. Your text is saved in this browser automatically.

  3. Save your work

    Copy it or download it as a file with the right extension.

About the JavaScript Viewer

Paste or open JavaScript to read it with syntax highlighting and folding. Use the JavaScript Beautifier to un-minify it first.

Built for developers

Why developers use it

  • Private by design

    Runs 100% in your browser. Nothing you paste is uploaded, logged or stored on a server.

  • Instant results

    Output updates as you type, with precise error locations when something is wrong.

  • Works offline

    Once loaded, the tool keeps working without a connection. Install it as an app if you like.

  • Free, no sign-up

    No accounts, no limits, no watermarks.

FAQ

Frequently asked questions

Is my data uploaded anywhere?

No. Everything runs locally in your browser — nothing you type, paste or open is sent to a server, logged or stored. The tool keeps working offline once the page has loaded.

Keep going

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