TestXSLT is the Apache Software Foundation's Xalan Java XSLT processor packaged for the Mac! Also on this page are JSP XML tags and a small class for JAXP developers.

FastXML is a prototype of component software for processing XML and XSLT that is compatible with MSXML and optimized for speed. The developer claims the program is about five times faster than MSXML.

The purpose of XSLTunit is to provide a unit testing framework for XSLT transformations similar to the "*unit" environments available for other languages (i.e. Junit for Java).

A text based tool to debug stylesheets and it is similar to the Unix/Linux debugger gdb. It uses using the libxslt library.

Xalan is an XSLT (Extensible Stylesheet Language Transformation) processor for transforming XML documents into HTML, text, or other XML document types. Has various versions (C++, Java) available. (Was initially called LotusXSL by IBM Alphaworks)

A package collecting the tools required for writing basic XML applications in Python, along with documentation and sample code. Features include (but are not limited to) SAX, DOM, the xmlproc validating parser, and an Expat interface.

IDE for open source languages, offering advanced support for Perl, PHP, Python, Tcl, and XSLT.

Libxslt is the XSLT C library developed for the Gnome project. Libxslt is based on libxml2 the XML C library developed for the Gnome project. It also implements most of the EXSLT set of extensions functions and some of Saxon's evaluate and expressions extensions. People can either embed the library in their application or use xsltproc the command line processing tool. This library is free software and can be reused in commercial applications (see the intro). Includes a link to a tutorial.

Visual XSLT is an XSLT development environment plug-in for Visual Studio .NET. Features include XSLT Debugger, XSLT Editor, Class Browser, Source Code Control, Project Manager, and Online Help.

The XSLTDoc Application helps you to browse and understand XSLT stylesheets. It shows summaries of stylesheets and explains each XSLT instruction in detail. This page also has several other useful utilities.

A powerful editor with XSLT processing and debugging capabilities. You can run an XSLT processor on the Emacs buffer you edit, and view the results either in another Emacs buffer or in a browser.

PSGML is a GNU Emacs Major Mode for editing SGML and XML coded documents. PSGML has several functions for editing SGML documents. Indentation according to element nesting depth and identification of structural errors (but it is not a validating SGML parser). Menus and commands for inserting tags with only the contextually valid tags. Attribute values can be edited in a separate window with information about types and defaults. Structure based editing includes movement and killing; and also several commands for folding editing.

SAXON is an XSLT processor developed by Michael Kay.

free servlet that uses XSLT to converts XML source into content (HTML, WML, XML, ...) viewable for the device.

A collection of Python tools for XML processing and object management. Features a repository, a rules-based engine, XSLT, XPath, RDF-based indexing and XLink resolution.

A couple of online utilities for converting XML and DTDs to XSL.

Alphaworks tool that can generate scripts in XSLT from mappings defined using a visual interface.

Commercial IDE for creating, validating, and debugging XSL, and XML-to-XML mappings. Integrated XSLT, Java, and MSXML debugger.

An optimizing XSLT compiler for Java, which turns stylesheets into binary Java classes.

A developer product implementing various XML-enabling technologies, which include a parser, writers, DOM, XPath, XSLT, XSLT extensions, XML-enabling extensions for ECMAScript (Javascript). The ECMA extensions are contained in a runtime library which must be redistributed.

A terse notation for writing complex XSLT stylesheets. The XSLScript script gets compiled into a corresponding XSLT stylesheet and then the generated XSLT stylesheet is applied.

An XSL/XSLT IDE and debugger based on MSXML. Trial download and purchasing information.

The Schematron is an XML structural validation language that uses patterns in trees instead of being based on grammars. Tested to work with the following XSLT implementations: MSXSL, SAXON and Oracle work fine. XT, Xalan, and Sablotron can work with certain caveats. Plenty of source code.

Parses XSL Transformational sheets. It uses XML::Parser and XML::DOM. Project inforamtion, man page, and downloads.

Tool to debug XSL transformations which is part of Stylus Studio. [Commercial]

Tool to debug XSL transformations. No longer maintained, but probably still useful. [Freeware]