Minify / beautify

About Minify / beautify

Minifies or pretty-prints HTML, CSS, and JavaScript in your browser without sending your source to an online formatter.

Minifiers and beautifiers on the internet are convenient until the snippet is a proprietary widget, a licensed stylesheet, or a bundle you cannot put on someone else's disk. I wanted the three formats I actually paste in a hurry: HTML, CSS, and JavaScript. Pick a mode, pick minify or beautify, paste. HTML and CSS minify are conservative whitespace and comment passes in the tab. JavaScript uses terser. Nothing phones home with your source. Turn the network off after load and the buttons still work, which is the whole privacy story.

Beautify uses js-beautify with two-space indent and a newline at the end, the same defaults I reach for when a minified file lands in chat and I need to read it. Minify won't fix broken syntax. Invalid JavaScript returns terser's error. I didn't add TypeScript, JSX, JSON, or YAML here; those have their own pages or their own parsers, and pretending one button covers every language is how formatters lie. JSON belongs on the JSON formatter; YAML belongs on the YAML converter. Switch modes before you paste if you changed languages mid-task; the button labels are explicit so you do not minify CSS with the HTML pass by mistake.

HTML minify is not a security sanitizer and not a template engine. It removes HTML comments and squeezes whitespace between tags; it won't rewrite your DOM for accessibility or strip scripts you left in on purpose. JavaScript minify keeps names unmangled by default so a quick shrink is readable enough to diff. If you need aggressive mangle and dead-code elimination for production, run your real build tool. This is the in-tab tidy pass before a paste or a quick size check. Pair with text diff if you want to see what minify changed besides fewer spaces. Load a file from disk if you prefer; the source still never uploads.

How to use Minify / beautify

1. 1Choose HTML, CSS, or JavaScript, then Minify or Beautify.
2. 2Paste the source into the input panel.
3. 3Copy the output, or read the error if the parser rejected the input.

What it won't do

• ·HTML, CSS, and JavaScript only. No TS, JSX, JSON, or YAML.
• ·HTML minify is whitespace-level, not a semantic HTML optimizer.

Common questions

Related tools

• JSON formatterPretty-print, minify, and validate JSON, with the parse error's line and column.
• Markdown previewType Markdown on the left, see the rendered page on the right.
• Text diffTwo panes, word-level inserts and deletes, no upload.