w3c validator

HTML Markup Validation Bookmarklet


Try Semtex – the new HTML5, CSS3 and JavaScript UI framework!

Acid.JS Validator is a free bookmarklet that uses the W3C SGML parser’s API to validate the markup of the page on which it is called. To start using the bookmarklet, go to this page and follow the instructions.

To validate a page, simply click the bookmark and you will be presented with a detailed validation report. In you are a chrome user, you can get and install the bookmarklet from Google Web Store.


Validation Success


Validation Failure


Site Cannot be Checked


Supported Browsers *

  • Mozilla Firefox
  • Google Chrome

* More browsers will be supported soon

To get your HTML markup validation bookmarklet, go to this page and follow the instructions.



New Features of W3C Validator.JS

Two new features are already available with W3C Validator.JS – Bulgarian language version (still incomplete, but I will finish it in the next few days) available from a link in the footer and in the context menu, and option for adding validation link and image to W3C Validator.JS from other websites, so their visitors can validate the code via W3C Validator.JS.

The excellent set of 88 x 16 web badges is provided by http://www.validationicons.com/:

 Valid XHTML 1.1

Visit this page to learn more about the validator, or go directly to its website and use it to validate your markup.

Visit http://acidmartin.wemakesites.net – the home of Acid.JS – The AJAX Tools and Widgets Library

W3C Validator.JS – Real AJAX Markup Validation Service

I’ve just finished my latest AJAX project – W3C Validator.JS. It is a real (x)html markup validator, that uses the W3C API for head requests. Except my own work on that website, W3C Validator.JS also utilizes two excellent AJAX/JSON scripts created by Jacob Seidelin of Nihilogic and Simon Wilson’s JSON-HEAD.

You may also put a validation link to W3C Validator.JS directly from your website using the following URL:

<a href="http://validator.wemakesites.net/#http://www.yourwebsite.com" rel="validate" title="Validate my Markup via W3C Validator.JS">Valid Markup</a>

To illustrate this, click the following link to validate my WordPress blog (unfortunately its markup is invalid).

Have fun with W3C Validator.JS!