Online YUI Compressor

Compress your assets by using yui compressor online. Support CSS and Javascript.


Minified Results

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Minified Results  Compression Ratio:

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The YUI Compressor is always to preserve the operational qualities of the code while reducing its overall byte footprint (both in raw terms and after gzipping, as most JavaScript and CSS served from production web servers is gzipped as part of the HTTP protocol). The YUI Compressor is JavaScript minifier designed to be 100% safe and yield a higher compression ratio than most other tools. Tests on the YUI Library have shown savings of over 20% compared to JSMin (becoming 10% after HTTP compression). The YUI Compressor is also able to compress CSS files by using a port of Isaac Schlueter 's regular-expression-based CSS minifier.

The YUI Compressor is written in Java (requires Java >= 1.4) and relies on Rhino to tokenize the source JavaScript file. It starts by analyzing the source JavaScript file to understand how it is structured. It then prints out the token stream, omitting as many white space characters as possible, and replacing all local symbols by a 1 (or 2, or 3) letter symbol wherever such a substitution is appropriate (in the face of evil features such as eval or with , the YUI Compressor takes a defensive approach by not obfuscating any of the scopes containing the evil statement) The CSS compression algorithm uses a set of finely tuned regular expressions to compress the source CSS file.