CKEditor (formerly known as FCKeditor) is a WYSIWYG rich text editor which enables writing content directly inside of web pages or online applications.

[8] The first version of CKEditor, under the name FCKeditor, was released in March 2003 by Frederico Caldeira Knabben, the creator of the editor and the project's Benevolent Dictator for Life.

After reaching more than 3 million downloads,[citation needed] FCKeditor was completely reviewed and redesigned into CKEditor 3, with special attention given to performance, accessibility and a new UI.

[9] In December 2012, CKEditor 4 was released with an Inline Editing solution, reformatted source code, enhanced DOM and CSS performance.

As of 2023 it consists of the following products: CKEditor 4 has features found in desktop word processors such as styles formatting (bold, italic, underline, bulleted and numbered lists), tables, block quoting, web resource linking, safe undo function, image inserting, paste from Word and other common HTML formatting tools.

[16] CKEditor 4 is fully compatible with most web browsers, including latest stable releases of Google Chrome, Firefox, Safari, Microsoft Edge, Opera and Internet Explorer 10 and 11.