Blogidate bookmarklet: 1-click blog post validation

"Blogidate" is a new bookmarklet that lets you validate the HTML in a blog post before posting it. It works in Mozilla but not in IE or Opera. To use it, choose the version that matches your blog's doctype and drag it to your bookmarks toolbar.

Here's a textarea so you can test the bookmarklet on this page:

The blogidate bookmarklet uses the WDG Validator rather than the W3C Validator because WDG's supports direct input. The two validators have few differences in what errors they flag.

Blogidate doesn't work in IE 6 because of IE 6's limit on bookmarklet length. It doesn't work in Opera 7 because Opera doesn't support document.forms on pages created by JavaScript.

I have tested blogidate with Movable Type and Blogger, and I expect it to work with other blog software.

snowchyld suggested the name "blogidate".

9 Responses to “Blogidate bookmarklet: 1-click blog post validation”

  1. Ariel Says:

    Using a Firebird nightly from a couple days ago, I get “No Textarias to Validate!”

    how is this supposed to work? am I doing something wrong?

  2. Simon Willison Says:

    I like the idea, but I’m not too keen on popping up a new window with an external validation service. How about an alternative bookmarklet that just validates XML well-formedness (essential for those of us who use XHTML)? I’ve been trying to figure out if that’s possible in Mozilla using the DOMParser object, but it doesn’t look like there’s a way of getting it to tell you if XML is ill-formed. I reckon it would be possible to build such a thing using the Gazingus native javascript XML parser from but you’d need to load it separately using the DOM/script append method as it’s way too big to fit in a bookmarklet.

  3. Anne van Kesteren Says:

    Just for the record, well-formed XML is not valid XHTML. <blockquote>This is quoted text</blockquote> is well-formed, but not valid.

  4. alanjstr Says:

    Error: open() has no properties
    Source File: javascript:( [removed] )
    Line: 1

    Double clicking it in the js console brings up a dialog that says “no text areas to validate”

  5. alanjstr Says:

    I can’t get it to repeat more than once per session. It doesn’t even work on this comment box at the moment. The XML well-formedness one works, though.

  6. alanjstr Says:

    Oh, that last one was cause I forgot to click OK on that dialog.

  7. snowchyld Says:


    tada.. i got to name something nifty if you blog, you should use this.. validation errors are primarily caused by hosed input into blog, and not the engine itself… Jesse Ruderman gives this blog snippet life and even pointed out…

  8. Jim Mangan's Weblog Says:


    Jesse Ruderman Blogidate is a new bookmarklet that lets you validate the HTML in a blog post before posting it….

  9. Roland Tanglao's Weblog Says:

    Jesse Ruderman: Blogidate XML well-formedness

    (SOURCE :”jonu”)- Cool hack! Gotta try this.