CSS Formatter — Pretty-Print and Beautify CSS Online
🔒 Runs in your browser — nothing is sent to a serverCSS formatter that pretty-prints any minified or hand-compressed stylesheet into a clean, readable structure with proper indentation in a single click. Paste a Tailwind purge output, a Bootstrap bundle, an SVG-icon stylesheet or any single-line CSS blob, and this CSS beautifier parses the source, places each declaration on its own line with a configurable 2-space, 4-space or tab indent, splits comma-separated selectors onto their own lines for readable diffs, indents nested at-rules (`@media`, `@supports`, `@keyframes`) and supports modern CSS Nesting. Comments, license `/*! ... */` blocks, CSS variables, vendor prefixes and `!important` are all preserved verbatim. Everything runs 100% inside your browser; your input never leaves your device, nothing is uploaded, logged or sent to any server.
When to use a CSS formatter online
You reach for a CSS formatter any time a single-line production bundle, a Tailwind purge output, a UI-library theme override or a copy-pasted snippet from DevTools arrives unreadable. Beautifying makes diffs reviewable in code review, lets you scan for a specific declaration without IDE help, and prepares CSS for inclusion in documentation, blog posts or design-system specs. Browser-local formatting matters when the source contains unreleased design tokens, white-label brand colors or internal-only admin themes — the stylesheet never travels to a remote SaaS formatter, never gets logged and never gets cached.
How CSS pretty-printing works under the hood
CSS pretty-printing is a parse-and-render pipeline. A small in-browser tokenizer walks the input character by character, tracking string literals, comments, parenthesised content (`url(...)`, `calc(...)`, `:nth-child(...)`) and brace depth. The tokenizer emits a tree of selectors, declarations and at-rules; comments attach to the next node so they survive into the output. The renderer walks the tree, places each declaration on its own line at the configured indent, splits comma-separated selectors so each lands on its own line for diff-friendly review, indents nested at-rules and CSS Nesting blocks one level deeper than the parent, and inserts a blank line between top-level rules. Identifiers are preserved exactly — vendor prefixes, custom properties, `!important` and license comments all survive untouched. The whole pipeline runs inside the browser engine in milliseconds, even on multi-thousand-line stylesheets.
Examples
.btn{padding:10px;color:#fff;background-color:#2563eb}.btn:hover,.btn:focus{background-color:#1d4ed8}@media (min-width:768px){.btn{padding:14px 20px}}.btn {
padding: 10px;
color: #fff;
background-color: #2563eb;
}
.btn:hover,
.btn:focus {
background-color: #1d4ed8;
}
@media (min-width:768px) {
.btn {
padding: 14px 20px;
}
}:root{--brand:#ff8800;--gap:16px}.banner{background:var(--brand) !important;padding:var(--gap);-webkit-backdrop-filter:blur(8px);backdrop-filter:blur(8px)}:root {
--brand: #ff8800;
--gap: 16px;
}
.banner {
background: var(--brand) !important;
padding: var(--gap);
-webkit-backdrop-filter: blur(8px);
backdrop-filter: blur(8px);
}.css-formatter{content:"css formatter";font-family:"Inter",sans-serif;color:#112233;padding:.5rem}.css-formatter {
content: "css formatter";
font-family: "Inter", sans-serif;
color: #112233;
padding: .5rem;
}.card{padding:12px;border:1px solid #ccc;&:hover{border-color:#888}& .title{font-size:1.25rem}}.card {
padding: 12px;
border: 1px solid #ccc;
&:hover {
border-color: #888;
}
& .title {
font-size: 1.25rem;
}
}