Version 55 (modified by jean-gui, 6 years ago)


What is Unicorn

W3C, home to the development of the technical specifications known as Web Standards, historically also provides online tools and services to check that content published on the Web follows these specifications, as well as a number of other tools to improve the global quality of Web sites. The most popular are the Markup Validator, CSS Validator, Link Checker...

All these services are individually useful, but it is often cumbersome for developers of Web content to use them all sequentially and test as many aspects of Web quality as possible. Unicorn aims to provide the big picture about the quality of a Web page, by gathering the results of all these tools into a single page.

Unicorn does not replace each individual validator, it unifies them, and increases their usability by providing a one-step check for the many facets of Web Quality and Web Standards Conformance.

Use it

  • The official, stable Unicorn is available at
  •  A development version is also available. This version contains the latest changes made to Unicorn's code base, but might be unstable or contain broken features.
  • As an open-source software, everyone can freely download, install and use Unicorn. More information is available in the installation documentation?.

To get more information on Unicorn's features and how to use it, make sure to check the documentation?.

Get involved

Feedback and bug reports

To make Unicorn better, we need user and developer feedback. Even if you're not a programmer, bug reports, ideas and suggestions are more than welcome.

For bug reports, feature request and feedback, please feel a new ticket in the issue database.

Translate it

Unicorn is available in many different languages. If your native language is not yet available or complete, or if you want to provide a better translation, Unicorn offers an easy to use  translation user interface.

Code contribution

Unicorn is an open source software tool developed in Java. If you want to play with the Unicorn code and help its development:

Validators contribution

If you are the developer of an online validator or a Web quality checking tool, you may want your tool to become an observation module plugged into Unicorn. As a quick start, a tutorial is available. For a more thorough documentation, check out the observers documentation?.