CSS / JS / HTML Minifier
Minify or beautify CSS, JavaScript, and HTML in your browser — no server, no external libraries. View compression ratio and byte savings instantly.
How It Works
CSS Minifier
Removes comments, strips redundant whitespace, eliminates trailing semicolons, and collapses spaces around selectors and properties — all with pure regex.
JS Minifier
Strips single-line and block comments, collapses whitespace, and removes spaces around operators. Conservative approach — safe for most JS without AST parsing.
HTML Minifier
Strips HTML comments, collapses whitespace between tags, and normalises attribute spacing — keeping your markup valid and functional.
What is CSS / JS / HTML Minifier?
A code minifier is a front-end performance tool that strips unnecessary characters from CSS, JavaScript, and HTML source code — including whitespace, comments, newlines, and redundant syntax — to produce a smaller file that loads faster in the browser. Minification is a standard step in modern web development build pipelines, and understanding what it does helps developers make better decisions about their code structure and delivery.
Reducing file size directly impacts page load time. Even a few kilobytes saved on a CSS or JavaScript file translates to fewer bytes transferred over the network, faster parsing by the browser, and a snappier experience for users on mobile or slower connections. For JavaScript specifically, minification also shortens variable and function names, further reducing file size beyond what whitespace removal alone achieves.
This tool works in both directions. In minify mode, it compresses your code and shows the original size, minified size, and percentage reduction so you can measure the impact. In beautify mode (also called pretty-print or format), it takes minified or poorly formatted code and reformats it with consistent indentation and spacing, making it readable again for debugging or review. This dual functionality makes the tool valuable not just for deployment preparation but also for inspecting third-party code.
How to Use CSS / JS / HTML Minifier
- Paste your code
Paste your CSS, JavaScript, or HTML code into the editor. The tool automatically detects the language or you can select it manually.
- Choose minify or beautify
Select minify to compress the code for production, or beautify to reformat minified or messy code for readability.
- View compression stats
See the original size, output size, and percentage saved. A clear indicator shows how much the minification helped.
- Copy or download the output
Copy the processed code to your clipboard or download it as a file ready to use in your project.
Key Benefits
Smaller files mean less data over the network and quicker parsing, directly improving page performance scores.
One tool handles both directions: compress for production or reformat for debugging and code review.
Instantly see original size, minified size, and percentage reduction to quantify the performance gain.
Supports CSS, JavaScript, and HTML in one place, covering the core front-end technologies in a single tool.
Frequently Asked Questions
Yes, minification only removes characters that do not affect execution. However, always keep a copy of the original source code. Most modern build tools like webpack and Vite minify automatically.
Standard CSS minification is safe. It removes comments, whitespace, and redundant semicolons without changing selector specificity or property values. Test the output in your target browsers before deploying.
Minification reduces the source code character count by removing unnecessary syntax. Compression (like gzip or Brotli) is a separate server-level step that compresses the file during transfer. Both are often used together.
Beautify restores indentation and line breaks, but cannot recover original variable names or comments because those are permanently removed during minification. It is useful for readability but not for restoring original source.