Stylus to CSS Compiler Online — Free Tool

Compile Stylus indented syntax back to standard CSS — braces and semicolons added automatically. Replaces the stylus CLI for quick conversions. 100% in your browser.

Input Stylus

CSS Output

What is a Stylus to CSS Compiler?

A Stylus to CSS compiler takes the indented .styl source format and emits standard CSS — adding the braces and semicolons that Stylus makes optional. The OpenFormatter version runs entirely in JavaScript and replaces the official stylus CLI for the common case where you need a quick conversion without installing Node tooling.

Stylus is concise but the resulting .styl files are not valid CSS — browsers, design systems, and CDN pipelines all expect plain CSS. This compiler closes that gap in your browser, no install required.

How to convert Stylus to CSS — 4 steps

Paste your Stylus. Drop a .styl file into the Input panel, or click Load Sample to try a navigation example.
Click Convert. The compiler walks each indent block and wraps it in braces, then appends semicolons to every declaration.
Review the CSS. Confirm each selector has a matching brace pair and every declaration ends with a semicolon.
Save as .css. Copy the output, save it as .css, and link it from your HTML — no preprocessor needed.

Sample Stylus in, CSS out

Input — Stylus

.nav
  display: flex
  align-items: center
  padding: 12px 24px
  background: #1a1a1a

.nav a
  color: #fff
  margin-right: 16px
  text-decoration: none

.nav a:hover
  color: #66ccff

Output — CSS

.nav {
  display: flex;
  align-items: center;
  padding: 12px 24px;
  background: #1a1a1a;
}
.nav a {
  color: #fff;
  margin-right: 16px;
  text-decoration: none;
}
.nav a:hover {
  color: #66ccff;
}

Indent to Braces

The compiler tracks indentation depth and emits braces wherever a block opens or closes — same logic the stylus CLI uses.

Browser-Ready Output

Output is plain CSS that runs in every modern browser. No preprocessor, no build step, no Node install required.

Client-Side Only

Conversion runs in JavaScript inside your browser. Source files never leave your machine.

Common use cases

check_circleMigrating a Stylus codebase off the preprocessor to a plain-CSS pipeline
check_circleDebugging compiled output without running the stylus CLI locally
check_circleShipping standalone .css to a project without stylus-loader configured
check_circleProducing CSS for design-system documentation snippets
check_circleConverting Stylus snippets from a tutorial back to copy-pasteable CSS
check_circleAuditing the final CSS a Stylus build would emit
check_circleBootstrapping a CSS framework starter kit from existing .styl files
check_circleQuick checks before committing whether the compiled CSS matches expectations

When to compile Stylus vs use the CLI

For one-off conversions and quick syntax checks, this browser compiler is faster than installing Node, the stylus npm package, and configuring a build. For full mixin expansion, function evaluation, or @import resolution across a multi-file project, the official stylus CLI remains the right tool — it executes the Stylus runtime, not just the syntax translation. Use this tool to migrate, share snippets, or sanity-check; use the CLI when you need full evaluation.

Need to go further?

Compile, format, or convert between every CSS preprocessor — all browser-side.

CSS to Stylus SCSS to CSS CSS Beautifier

Frequently Asked Questions

Is Stylus still maintained?

Stylus is still actively published on npm but development has slowed substantially compared with SCSS and LESS. Many newer projects pick Sass or PostCSS instead. If you inherit a Stylus codebase, this compiler lets you migrate selectively without forcing the whole project to switch.

Why convert Stylus to CSS?

Three reasons: migrating off Stylus to a build-tool-free CSS pipeline, debugging compiled output without running the stylus CLI, and shipping a standalone .css file to a project that does not have stylus-loader configured. The compiler runs entirely in your browser so there is nothing to install.

How are Stylus mixins handled?

Mixin definitions and @include calls are syntactic constructs that require Stylus runtime evaluation — this client-side compiler does not execute them. Inline the mixin output manually before pasting, or run the official stylus CLI for full mixin expansion. The converter focuses on the syntax-translation step (indent to braces).

Does it support the optional colons and braces in Stylus?

Yes. Stylus accepts color #fff (no colon), color: #fff (with colon), and even brace blocks. The compiler normalises both colonless and colon forms to standard CSS and emits explicit braces around every block.

How are nested selectors converted?

Stylus tracks structure by indentation. The converter detects when a child block is more indented than its parent and wraps the parent in braces. Each declaration line gets a semicolon. The output is flat CSS — nested rules are emitted as descendant selectors only when an explicit & operator is used (which requires a Stylus runtime to expand).

Can I run the output in any browser?

Yes. The output is plain CSS that runs in every modern browser without preprocessing. Drop it in a <style> tag, link it as a .css file, or paste it into your design system.

Does the converter handle @media queries?

Yes. @media (min-width: 768px) blocks are wrapped in braces and the indented declarations are emitted with semicolons. Nested @media inside selectors becomes a wrapped block in the output.

Is my Stylus source uploaded anywhere?

No. The compiler runs entirely in your browser as JavaScript. Source files containing internal class names or design tokens never leave your machine. Verify in DevTools — the Network tab stays empty while compiling.