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Minifieur CSS/JS

Minifier et embellir le code CSS et JavaScript

Entrée
CSS
Sortie

Comment utiliser

1

Collez ou saisissez du texte

Entrez votre texte, code ou données dans la zone de saisie.

2

Choisissez les options

Sélectionnez la transformation ou le format que vous souhaitez appliquer.

3

Copiez le résultat

Copiez la sortie dans votre presse-papiers en un clic.

Pourquoi utiliser cet outil

100 % Gratuit

Aucun coût caché, aucun niveau premium — chaque fonctionnalité est gratuite.

Aucune installation

Fonctionne entièrement dans votre navigateur. Aucun logiciel à télécharger ou installer.

Privé et sécurisé

Vos données ne quittent jamais votre appareil. Rien n'est envoyé sur un serveur.

Fonctionne sur mobile

Entièrement adaptatif — utilisez-le sur votre téléphone, tablette ou ordinateur.

CSS and JavaScript Minification for Web Performance

Key Takeaways

  • Minification removes whitespace, comments, and unnecessary characters to reduce file sizes by 20–60% on average.
  • Smaller CSS and JavaScript files mean faster page loads, especially on mobile networks with limited bandwidth.
  • All minification runs in your browser — your source code stays completely private.

Every kilobyte matters for web performance. CSS and JavaScript minification is a fundamental optimization that strips unnecessary characters from source code without changing functionality. While build tools like Webpack and Vite handle this automatically in production pipelines, a quick online minifier is invaluable for one-off optimizations, email templates, and embedded scripts.

Minification typically reduces CSS file sizes by 20–40% and JavaScript by 30–60%.

Size Reduction

Common Use Cases

1

Email Template Optimization

Minify inline CSS in HTML email templates to stay under email client size limits and improve rendering speed.

2

Third-Party Script Embedding

Minify JavaScript snippets before embedding them as inline scripts in CMS platforms or widget integrations.

3

Performance Auditing

Quickly check how much size reduction minification would achieve for files flagged in Lighthouse performance audits.

4

CDN Payload Optimization

Minify static assets before uploading to CDNs that do not offer automatic minification at the edge.

Pro Tips

Always keep your original unminified source files in version control — minified code should only be used in production.

Combine minification with gzip or Brotli compression for maximum file size reduction — they complement each other well.

Test minified code thoroughly, as aggressive minification can occasionally break CSS specificity or JavaScript variable scoping.

Use source maps in development to debug minified code by mapping it back to the original readable source.

All CSS and JavaScript minification is performed entirely in your browser. Your source code is never uploaded to any server, ensuring your proprietary code and business logic remain completely private.

Questions fréquentes