Pretty Diff - The difference tool


Use this free open-source file comparison tool to accurately diff between file versions regardless of comments or minification to the whitespace. This tool is written entirely in JavaScript and it can also beautify (pretty-print) and minify HTML. Since this tool is client-side JavaScript only, meaning that the execution occurs on the local computer only and the resulting output is not transmitted or stored, it is safe for processing classified information. Please note that this tool is not a validation service. Pretty Diff is a language aware code comparison tool featuring automatic language detection. Some of the supported languages include: XML, SGML, JSTL, HTML, CSS, SCSS, CSV, JavaScript, and JSON

Confidential: This tool executes entirely on the client computer without leaking any submitted data over the internet.

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Reporting data which updates with each use of the tool

Diff Report

Beautify Report

Minify Report

Usage Statistics

Main Options


Input display

Additional options

Base Text

New Text

Please post comments, feedback, and requests on the Pretty Diff mailing list.

If you get bored go check out my other projects: Mail Markup Language, Slideshow, and JSGUI (Incomplete).

Created by Austin Cheney on 3 Mar 2009. This is a heavy modification of JavaScript tools: jsdifflib, jsmin in JavaScript, cleanCSS and other custom written libraries.

Pretty Diff is used by these great organizations: