System Requirements

This website contains links to software which is either no longer maintained or will be supported only until the end of 2019 (CKFinder 2). For the latest documentation about current CKSource projects, including software like CKEditor 4/CKEditor 5, CKFinder 3, Cloud Services, Letters, Accessibility Checker, please visit the new documentation website.

If you look for an information about very old versions of CKEditor, FCKeditor and CKFinder check also the CKEditor forum, which was closed in 2015. If not, please head to StackOverflow for support.


CKFinder is compatible with the following browsers, with their default settings:

  • Internet Explorer 5.5+
  • Firefox 1.5+
  • Safari 3+
  • Opera 9.5+

Note for Opera: By default Opera is configured to not allow scripts to receive right click events. The context menu will not work because of this. To correct it, just enable this option in the Opera settings: Tools (Menu) > Preferences... > Advanced (Tab) > Content (Left List) > JavaScript Options... > Allow script to receive right clicks (must be checked).


CKFinder requirments for PHP:

  • PHP 4.3+ (including PHP 5.x and PHP 6.x).
  • GD extension enabled (default on most installations) for thumbnails support.
    Thumbnails are automatically disabled if this extension is missing. See
This page was last edited on 28 May 2010, at 08:46.