Code formatter & minifier — HTML, CSS, JS and XML
A code formatter reindents messy code so it is readable; a minifier does the reverse — it strips comments and whitespace so the file ships smaller and loads faster. Carbide gives you both for HTML, CSS, JavaScript and XML, running entirely in your browser with nothing uploaded.
This guide covers when to beautify versus minify, how to do each in a few clicks, and how much size minifying actually saves. Every tool below processes your code on your own device, so pasting production code stays private.
Beautify vs minify — what each does and when you want it
Beautifying (also called formatting or prettifying) adds consistent indentation, line breaks and spacing so a human can read and edit the code. You want it when you inherit a squashed file, when a tool spat out one-line output, or before you review a diff. Minifying does the opposite: it removes every byte a browser does not need — comments, spaces, newlines — to make the file smaller and faster to download.
The rule of thumb: beautify while you work, minify before you ship. The same Carbide tool usually handles both directions, so you can unminify a file to understand it, edit it, then minify it again for production. Nothing about your code leaves the tab in either direction.
- Beautify → readable, indented code for editing and review.
- Minify → smaller file, faster load, no readability.
- Both run in your browser — no upload, no sign-up, no file caps.
Format messy HTML with proper indentation
Paste a wall of unindented markup into the HTML formatter and it rebuilds the structure — nested tags indented, attributes lined up, one element per line — so you can actually see where a `<div>` opens and closes. It is the fastest fix for HTML copied out of a page source, a CMS export or an email template.
How to do it: open the HTML formatter, paste your HTML, and the beautified version appears instantly with proper indentation. Copy it back into your editor. Expected result: the same markup, unchanged in meaning, but readable — every tag correctly nested and indented so review and edits are painless.
Unminify CSS and JavaScript back to readable code
The most common real-world need is the reverse of minifying: you have a minified `.css` or `.js` bundle and you need to understand it. The CSS formatter expands compressed stylesheets back into readable rules with one selector per block, and the JavaScript beautifier reindents a squashed script so you can trace what it does.
This matters for privacy as much as readability. Pasting a production bundle into a random online tool means trusting a stranger's server with proprietary code — Carbide runs the beautifier in your browser, so the code never leaves your device. Paste the minified file, get formatted output, and read or debug it locally.
Beautify XML — read sitemaps, RSS and SOAP payloads
XML often arrives as one long line: a sitemap, an RSS feed, a SOAP response or a config export. The XML formatter reindents it into a clear tree so you can find the node you need without scrolling sideways forever. It also minifies XML when you need to send a compact payload.
To read a raw XML file: open the XML formatter, paste the content, and it renders a properly indented structure with each element on its own line. This is the quickest way to inspect a `sitemap.xml`, debug an API response, or check that a feed is well-formed — all handled in the browser, so business data in the XML is never uploaded.
Minify CSS and HTML safely — and see the size saved
When it is time to ship, the CSS minifier strips comments and whitespace and shows you the before-and-after byte size plus the percentage saved, so you know the win is real. Minified CSS commonly drops 15–30% of its size, which is fewer bytes to download on every page load.
The HTML minifier does the same for markup, but the important part is what it does not touch: it preserves inline scripts and styles so aggressive minification does not break your page. Paste your file, minify, copy the smaller output. Expected result: identical rendering in the browser, a smaller file, and a size-saved figure you can point to.
One tool per language — how to pick
Each language has its own tool so the formatting rules match the syntax exactly. Match the file type to the tool and you are done:
- Messy markup → HTML formatter; ship-ready markup → HTML minifier.
- Stylesheets → CSS formatter to read, CSS minifier to compress.
- Scripts → JavaScript beautifier to unminify and format.
- Feeds, sitemaps and configs → XML formatter.
- Working with data instead of code? Reach for the JSON formatter or compare two files with the diff checker.
Frequently asked questions
Does minifying my code break my site?
It should not. Minifying only removes comments and insignificant whitespace, leaving the code's behaviour identical. The HTML minifier in particular preserves inline scripts and styles so aggressive stripping cannot break your markup — the page renders exactly the same, just from a smaller file.
How much does minifying actually save?
It depends on the file, but CSS and JavaScript commonly shrink 15–30%, and heavily commented files save more. The CSS minifier shows the before-and-after byte size and the percentage saved, so you see the real number rather than a vague promise.
Is my code uploaded to a server?
No. The HTML formatter, CSS formatter, JavaScript beautifier and the minifiers all run in your browser — your code is formatted on your own device and nothing is sent anywhere. That is what makes it safe to paste proprietary or production code.
Can I unminify CSS or JavaScript back to readable code?
Yes. Paste a minified file into the CSS formatter or JavaScript beautifier and it reindents the code into readable rules and lines. It is the same tool that minifies, run in the other direction.
Are these formatters free?
Yes — every formatter and minifier here is free with no sign-up, no watermark and no file-size caps. Because the work happens in your browser, there is no server cost to gate behind an account.
Beautify while you build, minify before you ship — and let each language use its own tool. Start with the HTML formatter or JavaScript beautifier to make code readable, then the CSS minifier or HTML minifier to make it small, all free and all in your browser.