general purpose validators
The following validators will validate multiple microformats on a page:
Optimus microformats transformer and validator is a microformats transformer and validator that supports numerous microformats including hCard 1.0, hCalendar 1.0, hReview 0.4 (in progress), hAtom 0.1 (note: hAtom validation issues).
Please add issues to the optimus-issues page.
Google Rich Snippets Testing Tool
The Google Rich Snippets Testing Tool can parse several microformats from a given URL and produces reports showing errors and a preview of what properties it detects. It supports a subset of properties on some microformats, however is continuously updated with more support.
specific microformats validators
- The unofficial hCard Validator
- It's open-source and contributions are welcome! Please join the project and extend it to support more microformats.
Operator does a good job of compliant parsing for microformats in general, and includes a debug mode that can help identify errors in the structure.
There has been a suggestion to host an "official" microformats validator at microformats.org.
- hCard validator is open-source (BSD-licensed) and extensible enough to support other microformats (it's mostly a matter of hooking up XSLT templates that extract microformat data and find errors). The codebase is pretty clean, UI is internationalized.
Who wants to help make this happen, and what do you need?