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CSS/JS 压缩工具

压缩和美化 CSS 与 JavaScript 代码

输入
CSS
输出

使用方法

1

粘贴或输入内容

在输入区域输入您的文字、代码或数据。

2

选择选项

选取要应用的转换方式或格式。

3

复制结果

一键将输出结果复制到剪贴板。

为什么使用此工具

100% 免费

没有隐藏费用,没有付费等级——所有功能完全免费。

无需安装

完全在浏览器中运行。无需下载或安装任何软件。

隐私且安全

您的数据永远不会离开您的设备。不会上传至任何服务器。

支持移动设备

完全响应式设计——在手机、平板或桌面电脑上均可使用。

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.

常见问题