Tools to Check Microformats

How Does Validating Site Code helps your SEO? 

• mostly consistent display for your sites with many browsers (which display the one and same - unvalid - page very differently) and making your site more readable for different user agents
• helping exposing and repairing barriers to accessibility
• encouraging compliance with existing accessibility guidelines - such as W3C's Web Content Accessibility Guidelines (WCAG) or Section 508
• making websites accessible to all individuals, including those with disabilities
• demonstrating professional coding skills

Here are 3 interesting Schema Validators or Rich Snippets Semantic Markups Checkers as well as deep code validators that any SEO Auditor will definitely find useful in his/her SEO Audit.

1- Google Structured Data Test 

• You can find it under the Webmaster Tools or in the Google Structured Data Test external Link 
• You can either enter the Page URL or copy and Paste the code snippet to validate (test/Check) 
• You can also find examples and Previews of Structured Data (authors, Products, events, Music, people, recipes, reviews, etc.) 

2- Validome.Org 

• Allows validation of XML 1.0 documents according to W3C specifications. » XML Validator « 
• Standalone grammar validator for XML DTDs and Schemas. » DTD / Schema-Validator « 
• Advanced Feed-Validator for » RSS and Atom « 
• Validates your » Google Sitemap(s) « on XML conformity and specific requirements

3- XML Schema Validator 

• Lets you validate XML documents such as XHTML against the appropriate schemas.
• It performs a more accurate validation than the W3C validator.
•  If you send XHTML documents as text/html, you should also test them in XHTML Proxy.
• This service does not perform generic XML Schema validation.
• While it can verify the well-formedness of any XML document, validation is only available with the built-in schemas.
• This validator does not download any DTD or schema files, but relies on its own ones.
• You can validate XML documents by URL, by file upload or by direct input.
• You can validate fragments of XML documents. You can easily validate the page that is currently displayed in your browser with this bookmarklet.

4- hCard microformat Validator

This is an unofficial validator¹/conformance checker of the hCard microformat.

5- W3C Markup Validation

This validator checks the markup validity of Web documents in HTML, XHTML, SMIL, MathML, etc. If you wish to validate specific content such as RSS/Atom feeds or CSS stylesheets, MobileOK content, or to find broken links, there are other validators and tools available. As an alternative you can also try our non-DTD-based validator.