CodeIgniter4 can be installed in a number of different ways: manually, using Composer, or using Git. Which is right for you?

  • If you would like the simple “download & go” install that CodeIgniter3 is known for, choose the manual installation.
  • If you plan to add third party packages to your project, or want to keep CodeIgniter up to date easily, we recommend the Composer installation.

However you choose to install and run CodeIgniter4, the user guide is accessible online.


Before using CodeIgniter 4, make sure that your server meets the requirements, in particular the PHP version and the PHP extensions that are needed. You may find that you have to uncomment the php.ini “extension” lines to enable “curl” and “intl”, for instance.