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CSS Minifier

Minify CSS by removing comments, whitespace, and redundant characters to reduce file size.

CSS MinifierGratisPopularCSS & DevRuns in your browser

Works in your browser. What you paste or upload is processed on your device.

Key features of the CSS minifier

  • Removes whitespace, newlines, and indentation
  • Strips CSS comments
  • Removes redundant semicolons
  • Preserves CSS functionality completely
  • Shows original vs minified size and savings percentage

How to use the CSS minifier

  1. Paste your CSS

    Enter your CSS code into the minifier input area.

  2. Minify

    Click 'Minify CSS' to compress the code.

  3. Review the output

    See the minified CSS and the size reduction achieved.

  4. Copy minified CSS

    Copy the minified CSS for use in your production stylesheet.

  5. Deploy to production

    Replace your development CSS file with the minified version in your production build.

What is a CSS minifier?

The CSS Minifier compresses CSS code by removing all unnecessary whitespace, comments, and redundant code — producing a functionally identical but significantly smaller CSS file. Minified CSS loads faster, reducing page weight and improving Core Web Vitals scores.

CSS files are often written with generous spacing, comments, and indentation for readability. These additions are valuable during development but add unnecessary bytes in production. Minification typically reduces CSS file size by 20–50%, directly improving page load time.

Why use a CSS minifier?

CSS file size directly affects page load speed, which is a Core Web Vitals factor and Google ranking signal. Minifying CSS is a standard production optimisation that requires zero effort to apply and consistently reduces file size by 20–50%.

CSS minifier: frequently asked questions

Something else? Ask the team

Will minified CSS still work exactly the same?

Yes. CSS minification only removes whitespace and comments — it doesn't change any CSS rules, selectors, or values. The browser renders minified CSS identically to the original.

How much can CSS minification reduce file size?

Typically 20–50% reduction depending on how much whitespace and comments your original CSS contains. CSS with many detailed comments can see even greater reductions.

Should I minify CSS manually or use a build tool?

For production workflows, build tools like webpack, Vite, or Parcel should minify CSS automatically. This tool is ideal for quick manual minification, one-off files, or when build tools aren't available.

Can I minify CSS with source maps?

This tool produces a minified CSS string without source maps. For development with debugging support, use build tools that generate source maps alongside the minified output.

Is there a risk of minification breaking my CSS?

Minification tools are well-tested and rarely break valid CSS. However, some edge cases (certain vendor prefixes, calc() expressions) may occasionally cause issues. Always test minified CSS before deploying.

Each one opens on its own page and works straight away, with no sign-up.

Explorar más herramientas gratuitas:Generador de SchemaGenerador de etiquetas MetaGenerador de LLMs.txtBrowse all free tools

¿Quieres conseguir más menciones en la IA?

CSS Minifier is one piece of the puzzle. See how ChatGPT, Gemini, Perplexity, and Google AI Overviews actually view your brand, and get a prioritised list of fixes, with a free AEO & GEO audit from AI Rank Lab.

One check is a start. The audit checks the whole site.

Realizar una auditoría AEO y GEO gratuita or Ver precios.

  • Scores SEO, answer-engine (AEO) and generative-engine (GEO) readiness
  • Lists the fixes, page by page
  • Then track whether ChatGPT, Gemini, Perplexity and Google AI Overviews cite you
fieldnote.app4,571 credits

Site audit

fieldnote.app · SEO, AEO and GEO

Illustrative data
SEO
82
+6
AEO
64
+11
GEO
58
+9
Pages
48
Fixesby impact
  • /pricing · Missing H1High
  • /blog/guide · No FAQ schemaMedium
  • /llms.txt · Not foundMedium
  • /about · Meta description too longLow

See where your whole site stands

Paste your site. The free audit scores it for SEO, answer engines and generative engines, with the fixes.

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