# clean-css/clean-css

Fast and efficient CSS optimizer for node.js and the Web

Repository: https://github.com/clean-css/clean-css
Canonical: https://ross.abutalabs.com/products/clean-css
Homepage: https://clean-css.github.io/
Language: JavaScript
License: MIT
License Family: permissive
Topics: css, minification, optimization, css-optimizations, css-optimizer, clean-css
Last push: 2024-10-18T06:34:43+00:00

## Health v2 (maintenance only)
Score: 32/100 (v2, computed 2026-09-03T02:20:16.233290+00:00)
- activity 0, release rhythm 35, longevity 100
- inputs: {"age_days": 5666, "days_push": 684, "days_rel": null, "gap_med": null, "n_releases_24m": 0}
- flags: no_releases
- formula: round(0.45*activity + 0.35*rhythm + 0.20*longevity); archived -> min(score, 10)

## Adoption (not part of the score)
Stars 4200, forks 318 (observed 2026-08-28T04:08:38.946334+00:00)

## What it is
clean-css is a fast and efficient CSS optimizer and minifier for Node.js and modern browsers, offering multiple optimization levels, source map support, and a CLI utility. It is one of the best-performing CSS minifiers according to benchmarks, though it is now in maintenance mode.

## Use cases
- minify css files for production
- optimize stylesheets to reduce page load time
- inline and process @import rules in css
- generate source maps for minified css
- rebase relative image urls in css
- batch minify multiple css files from the command line

## When to choose
- you need a battle-tested, high-performance CSS minifier for Node.js or browser builds
- you want fine-grained control over optimization levels and formatting
- you need source map support and @import inlining during minification

## When to avoid
- you need a tool with active feature development, since clean-css is in maintenance mode
- you want a full CSS framework or preprocessor rather than a minifier
- your build pipeline already includes a modern bundler with built-in CSS minification

## Facets
- artifact type: library
- maturity: maintenance
- function: css-framework, build-tool, cli
- domain: web-development, frontend, developer-tools
- platform: browser, cli, cross-platform
- tags: css-minifier, css-optimizer, minification, source-maps, nodejs

## Member repositories
- clean-css/clean-css (main) score 32

## Provenance
- Observed fields: from GitHub, fetched 2026-08-28T04:08:38.946334+00:00.
- Health v2: computed from the inputs above; adoption is never an input.
- Inferred fields (summary, facets, guidance): AI-extracted, prompt v1, taxonomy v1, on 2026-08-29T18:22:33.104225+00:00, confidence not recorded.
  - readme: https://github.com/clean-css/clean-css (fetched 2026-08-28T04:08:38.946334+00:00, sha 9688a40aafe9)
  - homepage: https://clean-css.github.io/ (fetched 2026-08-29T09:13:08.227315+00:00, sha 7abd5b0f8d41)
  - registry_npm: https://registry.npmjs.org/clean-css (fetched 2026-08-29T09:13:08.251489+00:00, sha aeefd5d0c816)
- Data as of 2026-08-30T08:39:29.467469+00:00.