WritePHPOnline.Com - WritePHPOnline.Com is an online site that enables you to write code in PHP and view its output.
PHPTester.net - PHPTester.net gives developers and learners the ability to write their PHP code and get the output online.
3V4L - 3V4L is the best online PHP shell that you can use to write the PHP code and test it online.
OnlinePHPFunctions - OnlinePHPFunctions is a powerful online code tester that lets you add PHP source code and view its output on your favorite web browser.
Rapid PHP - Rapid PHP editor is the world's fastest and lightest PHP IDE for Windows with code intelligence and tools for PHP, HTML, CSS, and JavaScript, including PHP debugger, FTP/SFTP client, UTF-8 support and more.
PHP Sandbox - PHP Sandbox is one of the major online sites that provides a Development Environment for PHP equipped with a Composer Package.