CSS Tools
10 free tools · 100% client-side
Format, minify, and convert CSS, SCSS, LESS, and Stylus online with a professional editor experience.
Start here
Most-used CSS Tools
CSS Formatter
One stylesheet workspace, three engines: prettier for canonical formatting, js-beautify for unminifying broken bundles, and a minifier for the compact form — pick the mode in the rail.
SCSS / Sass to CSS
The real dart-sass compiler in a browser tab — mixins, functions, @use and nesting evaluated, not approximated.
CSS Preprocessor Converter
One page for every cross-dialect trip — LESS, SCSS, indented Sass and Stylus, in any of the twelve directions.
All 10 CSS Tools
CSS Formatter
One stylesheet workspace, three engines: prettier for canonical formatting, js-beautify for unminifying broken bundles, and a minifier for the compact form — pick the mode in the rail.
Minify CSS
Strip every byte the browser doesn't need — comments gone, whitespace collapsed, savings shown.
CSS Preprocessor Converter
One page for every cross-dialect trip — LESS, SCSS, indented Sass and Stylus, in any of the twelve directions.
CSS to LESS
Translate stylesheets from plain CSS to LESS — structure, variables and nesting mapped for you.
CSS to SCSS / Sass
Plain CSS into Sass — brace-and-semicolon SCSS or the indented .sass syntax, chosen with one toggle.
CSS to Stylus
Translate stylesheets from plain CSS to Stylus — structure, variables and nesting mapped for you.
LESS to CSS
less.js itself, running in your browser — mixins expanded, guards evaluated, colour functions computed.
SCSS / Sass to CSS
The real dart-sass compiler in a browser tab — mixins, functions, @use and nesting evaluated, not approximated.
SCSS ⇄ Sass Converter
The two Sass syntaxes, in either direction — braces and semicolons added or removed, everything else left exactly as written.
Stylus to CSS
Translate stylesheets from Stylus to CSS — structure, variables and nesting mapped for you.
Learn more
Every stylesheet dialect, one workspace
CSS work spans dialects: plain CSS in production, SCSS or LESS in the build pipeline, occasionally Sass's indented syntax or Stylus in inherited code. This hub covers the full matrix — formatters and minifiers for plain CSS, plus a complete grid of converters between CSS, SCSS, Sass, LESS, and Stylus in every direction, powered by real preprocessor engines rather than regex find-and-replace.
Conversions that go from a preprocessor to CSS compile the source — variables resolve, nesting flattens, mixins expand — so the output is exactly what your build would ship. Conversions between preprocessor dialects translate syntax (variable prefixes, mixin declarations, nesting style) while preserving the source's structure, which is what you want when migrating a codebase file by file.
When to format, when to minify, when to convert
Format when reading: a minified production stylesheet from DevTools becomes navigable in one click. Minify when shipping: whitespace and comments routinely account for 20–40% of hand-written CSS. Convert when migrating: moving from LESS to SCSS (the most common path), modernizing Stylus, or compiling a preprocessor file to vanilla CSS to drop a build step entirely. Each page documents its engine and the dialect features it understands, so edge cases like LESS guards or Sass placeholder selectors aren't silent surprises.
Help
Frequently asked questions
Everything you need to know about the CSS Tools.
01Are these real preprocessor compilers or text transformations?
Compilations to CSS use real engines — your SCSS/LESS/Stylus compiles exactly as in a build pipeline, with variables resolved and nesting flattened. Dialect-to-dialect conversions are structural translations that preserve variables and nesting as the target syntax; per-page FAQs note constructs that have no direct equivalent.
02Which should I migrate to: SCSS, LESS, or plain CSS?
In 2026 the gravity is toward SCSS for large design systems and plain modern CSS (custom properties, nesting, color functions) for everything else — native CSS now covers most of what preprocessors were invented for. The converters here make either migration incremental instead of big-bang.
03Does minifying CSS change specificity or behavior?
No — minification removes whitespace and comments and shortens what is provably safe to shorten. Selectors, property order, and the cascade are untouched, so the minified sheet renders identically to the source.
Learn the format
Guides for css tools
Sass vs SCSS vs LESS vs Stylus: Choosing a CSS Preprocessor
How Sass, SCSS, LESS and Stylus differ in syntax and modules, what native CSS nesting and custom properties replaced, and how to migrate between dialects.
9 min readGuide · Developer ToolsFreeFormatter Alternatives (2026): Where Its Tools Went
FreeFormatter.com has been retired and its tool pages now return 404. A verified map of where each formatter, validator, escaper and encoder moved.
6 min read