CRX Source Viewer

Instantly view, beautify and download the source code of any Chrome, Firefox, or Edge extension. Audit permissions & manifest.

CRX Source Viewer lets you instantly view, read, and download the source code of any Chrome, Firefox, or Edge extension — straight from its store page, no unzipping required. Open a listing, click View Source and every file inside the extension is right there: formatted, searchable and ready to inspect. 🆕 What's new in 1.1.0 - Firefox Add-ons and Edge Add-ons support — view source and download packages from all three stores, not just Chrome - New Analysis tab — audits every permission in plain English with risk levels, plus host access, content scripts, and manifest details - Auto-beautify for minified JavaScript, CSS, and HTML, with real, working settings - Interface now available in 30 languages, with light and dark themes - Download as a clean ZIP or the original signed package (CRX / XPI) - Reliability fixes and a refreshed icon What makes it different Most source viewers just extract the package and leave you staring at minified, unreadable code. CRX Source Viewer automatically beautifies minified JavaScript, CSS, and HTML the moment you open a file, so you can actually read what an extension does. And the built-in Analysis tab reads the manifest and explains every permission in plain English — with risk levels — so you can audit an extension's security and privacy before you trust it. Features ✅ View the source of any extension on the Chrome Web Store, Firefox Add-ons (AMO), or Edge Add-ons ✅ Auto-beautify minified JavaScript, CSS, and HTML into clean, readable code ✅ Analysis tab — permission risk audit, host-access breakdown, content-script inspection ✅ Syntax highlighting for JavaScript, TypeScript, JSON, HTML, and CSS ✅ Browse the full file tree; filter and search across every file (text or regex) ✅ Inspect manifest.json, permissions, content scripts, and background scripts ✅ Download as a clean ZIP or the original signed package (CRX / XPI) ✅ File integrity hashes — MD5, SHA-1, SHA-256, SHA-384, SHA-512 ✅ Open local .crx, .xpi, or .zip files by drag and drop ✅ Right-click any extension link to view its source ✅ Interface in 30 languages, with light and dark themes ✅ Fast, lightweight, and runs entirely in your browser How to view extension source code 1. Install CRX Source Viewer 2. Open any extension page on the Chrome Web Store, Firefox Add-ons, or Edge Add-ons 3. Click the CRX Source Viewer icon in your toolbar 4. Click View Source — then browse, read, search, and download, all in one place Why developers and researchers use it Extension developers use CRX Source Viewer to see how other extensions are built, learn from real-world code, and inspect the competition. Security researchers use it to check extensions for hidden trackers, data-collection scripts, and risky permissions before installing. Privacy-conscious users use it to see exactly what an extension can access before trusting it with their browser. CRX Source Viewer automatically detects the minified, compressed JavaScript that most published extensions ship and reformats it into clean, readable code with js-beautify — on every file, automatically. Privacy CRX Source Viewer collects no data. All source code is processed locally in your browser — no analytics, no tracking, no external servers. The only network request it makes is to each store's official download endpoint to fetch the extension you choose to inspect. Independent project — not affiliated with, endorsed by, or sponsored by Google, Mozilla, or Microsoft. Chrome Web Store, Firefox, and Edge are trademarks of their respective owners.