An open source PHP accelerator, encoder and dynamic content cache for PHP that also features an optional obfuscator. Features a standalone loader, an API, and installation notes. [Open Source]

Provides a PHP IDE for Windows, a regular expression debugger and code reformater application. [Commercial]

A full-featured profiler/debugger that is loaded as a zend_extension. It aims to be an analog of C's gprof or Perl's Devel::DProf. Offered from PHP.net [Open source, GPL]

Provides software and specifications for enabling n-tier development within PHP, such as the phpBeans Object Server, and interoperable with other languages as well. [Open source, GPL]

A PHP editor built on top of Visual Studio .Net .

Tool for writing and testing PHP and HTML pages. Offers Unicode support and file search utility. Website also contains related editing products for Perl and Powerpoint. [Shareware]

PHP unit tester and mock objects framework. [Open source, Open Group Test Suite License]

A complete IDE for creating, testing, and debugging PHP scripts that runs on Windows 9x/NT/2000/XP. The site also includes an Apache GUI and editors for CSS and Perl. [Commercial]

Editor for PHP, but also HTML, XHTML, CSS and JavaScript code with validation, reuse, navigation and formatting functions, syntax highlighting, PHP debugger, PHP function hints, file and FTP explorer, and code templates. [Shareware]

PHP debugger for stepping through code, breaking at errors and breakpoints. Site also contains full documentation, licensing information, and a "help out" section.[Open source, GPL]