1. Local Development Environment

• XAMPP/MAMP/WAMP: You can install a local server like XAMPP (for Windows), MAMP (for macOS), or WAMP (for Windows). These packages include Apache, MySQL, and PHP, allowing you to run PHP code on your local machine.
• VS Code with PHP Server Extension: You can use Visual Studio Code with the PHP Server extension to quickly run PHP code.

2. Online PHP Testing Tools

• PHP Fiddle: phpfiddle.org is an online tool that allows you to write and test PHP code directly in your browser.
• 3v4l.org: 3v4l.org lets you run your PHP code across different versions of PHP and see the output.

3. Command Line

• PHP CLI: You can run PHP scripts directly from the command line if PHP is installed on your system
  
  php your-script.php

 4. Integrated Development Environments (IDEs)

• PHPStorm: A robust IDE for PHP with built-in testing capabilities.
• NetBeans: Another IDE that supports PHP with integrated testing features.