CKEditor - Real-time collaborative future-ready rich text editor
TinyMCE - TinyMCE is a content editor that functions as a plug-in for Wordpress websites.
Quill - Powerful, API-driven rich text editor
Trumbowyg - Feature-packed WYSIWYG editor in only 15kB of JavaScript
Summernote - Summernote is a JavaScript library that helps users create WYSIWYG editors online.
CKEditor 4 - CKEditor 4 is a rich text editor that enables you to write content inside of web pages or online applications.