PurifyCSS Online - An online tool for removing unused CSS from stylesheets to improve website performance.
## Purpose of PurifyCSS Online
The primary purpose of PurifyCSS Online is to remove unused CSS from stylesheets, thereby reducing file size and improving website performance. It achieves this by analyzing HTML and JavaScript files to identify which CSS selectors are actually used, then generating a cleaned version of the CSS file containing only the necessary styles.
## Purpose of PurifyCSS Online
PurifyCSS Online improves website performance by:
- Reducing the size of CSS files by removing unused selectors, which decreases download time.
- Minimizing render-blocking resources, leading to faster page loading.
- Particularly benefiting mobile users by reducing bandwidth usage and improving load times on slower connections.
## Target Websites for PurifyCSS Online
Websites that benefit most from PurifyCSS Online include:
- Those using CSS frameworks like Bootstrap that include many unused styles
- WordPress sites with multifunction themes containing extensive CSS
- Single-page applications (SPAs) with dynamically loaded content
- Any website where CSS files contain significant amounts of unused code
## Features of PurifyCSS Online
Key features of PurifyCSS Online include:
- Browser-based operation requiring no installation
- Support for various development environments and CMS platforms
- Fast analysis and removal of unused CSS selectors
- Integration with JavaScript coverage tools
- Generation of optimized CSS files while preserving necessary styles
## Technical Basis of PurifyCSS Online
PurifyCSS Online is built upon the open-source PurifyCSS library developed by Ilias Ismanalijev. This library performs static analysis of code to detect used CSS selecters. The online version provides a user-friendly interface to this functionality without requiring command-line usage or npm installation.
## Usage Steps for PurifyCSS Online
To use PurifyCSS Online:
1. Visit https://purifycss.online/
2. Input your CSS file (via URL or upload)
3. Provide relevant HTML and JavaScript files (via URL or upload)
4. Initiate the purification process
5. Download the cleaned CSS file
## Limitations of PurifyCSS Online
Users should be aware of these potential limitations:
- May accidentally remove CSS for dynamic content or hover states
- Online version may have fewer features than the CLI version
- Requires careful verification of results, especially for complex websites
- JavaScript-dependent styles might be incorrectly identified as unused
## Comparison with Similar Tools
Compared to similar tools like UnCSS Online, PurifyCSS Online offers:
- Greater emphasis on user-friendliness for non-technical users
- Better support for CMS platforms like WordPress
- Integration with JavaScript coverage tools
- A simpler interface focused on basic optimization needs
While UnCSS Online may offer more advanced options for experienced developers.
## Maintaining Organization of PurifyCSS Online
PurifyCSS Online is part of webperftools.com, a platform offering various website performance optimization tools. The tool is based on the open-source PurifyCSS library available on GitHub.
## Supported Input Formats
PurifyCSS Online supports:
- CSS files (via direct upload or URL)
- HTML files (via direct upload or URL)
- JavaScript files (via direct upload or URL)
These inputs are necessary for the tool to properly analyze CSS usage patterns.
### Citation sources:
- [PurifyCSS Online](https://purifycss.online) - Official URL
Updated: 2025-04-01