Online PHP tester

You can choose between PHP: 5.2.17, 5.3.18, 5.4.8 And You have memory_limit = 128MB

List of HTTP header fields

http://en.wikipedia.org/wiki/List_of_HTTP_header_fields

PHP Coding Standards

PHP-FIG FAQ PSR-0 Autoloading Standard PSR-1 Basic Coding Standard PSR-2 Coding Style Guide PSR-3 Logger Interface Symfony2 Coding Standards

PHP Coding Standards Fixer

“The PSR-1 and PSR-2 Coding Standards fixer for your code” http://cs.sensiolabs.org/