Editor.js is described as 'block-styled editor for rich media stories. It outputs clean data in JSON instead of heavy HTML-markup. And more important thing is that Editor.js is designed to be API extendable and pluggable. So there are few key features: 1. Clean data output' and is a WYSIWYG Editor in the category. There are more than 25 alternatives to Editor.js for a variety of platforms, including Online / Web-based, Self-Hosted solutions, Internet Explorer, Safari and Opera. The best alternative is TinyMCE, which is both free and Open Source. Other great apps like Editor.js are CKEditor (Paid, Open Source), Trumbowyg (Free, Open Source), Aloha Editor (Free, Open Source) and CrossBrowdy (Free, Open Source).