JavaScript Beautifier
Beautify JavaScript — turn minified one-liners into readable code.
How to use JavaScript Beautifier
- Paste the JavaScript — a minified bundle, inline script or messy source.
- Read the formatted output — statements separated, blocks indented, flow visible.
- Expect short variable names in production code — minification renamed them permanently; structure still tells the story.
- For debugging live sites, DevTools' {} pretty-print does this with breakpoints — use both.
What is JavaScript Beautifier?
A JavaScript beautifier re-formats code into readable structure: statements on their own lines, blocks indented, operators spaced — turning the single 80,000-character line of a minified bundle into code a human can follow. Logic is untouched; only formatting returns.
The honest caveat up front: beautifying reverses the whitespace-stripping of minification but not the variable renaming — production bundles' function a(b,c){return b+c} beautifies into readable structure with unreadable names. Structure plus context is usually enough to follow the logic; original names need source maps.
About the JavaScript Beautifier
Paste minified or messy JavaScript and get indented, structured output — readable enough to debug, learn from or audit.
Why people beautify JS: debugging a production error whose stack trace points into a minified bundle (beautify, find the line, reason about it), understanding what a third-party script actually does before trusting it on a page (analytics snippets, ad tags, that widget marketing wants), inspecting a site's frontend logic out of curiosity or research, and reformatting legacy code written before Prettier standardized everyone's style.
In-browser alternative worth knowing: DevTools' pretty-print button ({}) does this inside the debugger with breakpoints attached. For code review, sharing or offline reading, a beautifier gives you the text itself. The reverse trip is the JavaScript Minifier; for deliberately scrambled (not merely minified) code, see the Deobfuscator.