Mercury Editor

Mercury is a full featured HTML5 editor. It was built from the ground up to help your team get the most out of content editing in modern browsers.

gem 'mercury-rails'
rails generate mercury:install

Check out the Demo View project on GitHub Download Mercury (v0.9.0)

Built to handle your content needs.


Mercury comes bundled as a Rails Engine, so just include it in your Gemfile. Or download the current bundled package if you're not using Rails.


We don't inject javascript or css into your production pages so you're free to use whatever frameworks you want without having to worry about conflicts.


Easily add or remove toolbar items or create entirely new tools. Any toolbar item can be tied to an action using behaviors and the command pattern.


Full HTML, Simple, Markdown, Snippet and Image regions are supported by default, but you can just extend the base regions to build your own types.


Built on top of the HTML5 contentEditable features, it natively supports the all the fancy new HTML5 elements, syntax, and JavaScript APIs.


Built for and maintained by the community via GitHub. You can track or report issues, contribute code or translations, and keep up with the project.

Chrome Firefox Safari Opera IE Mobile Safari

All browsers that implement the complete W3C contentEditable specification are supported.

Flexible and useful out of the box.

Full HTML Regions

Full HTML markup that utilizes the HTML5 contentEditable feature. These are the core of what Mercury Editor does, and provide the most flexibility.

Simple Regions

Plain text, newlines and markup aren't allowed. Appropriate for titles, headlines, or any area where you want just the content and not the styles.

Markdown Regions

Based on the Github flavored Markdown syntax. These are useful if you want to keep the markup flexible, while still clean and simple.

Snippets Regions

Allows snippets but not content. Snippets are chunks of reusable markup or code defined by a developer and can be placed into content later.

Image Regions

Only applied to image tags, it results in the image being drag-and-drop replaceable. Great for images you don't want within content regions.

Custom Regions

When the provided regions don't give you what you need, create your own based on your specific needs. You'll be the most appreciated developer.


Preview content while you're working to see exactly how it'll look.


Built in low profile translation and internationalization system.

Link Tools

Insert and edit links, including TOC & Bookmark links.

Media Tools

Insert and edit images, youtube videos, and vimeo videos.

Table Editing

Advanced visual table editing and creation within content.


Insert predefined reusable bits of markup using drag and drop.

Image Upload

Drag images from your desktop to automatically uploaded and insert them.


Build from the existing HTML, markdown, snippet, simple, and image regions.


Build on top of Rails and the asset pipeline. Watch the RailsCast for an introduction.


Tested using Jasmine and Cucumber to ensure production ready code.


Released under the MIT License so you can do what you want.


Made with love, contributed to by many amazing developers and designers.