W3 Validation

You want your site to be visible to the highest number of people, right? It needs to be W3 valid.

When one of your web pages is not W3 valid, browsers, like Safari, Internet Explorer, and Firefox, trying to read the page will have to wing it. Often the browsers do a good job (particularly with common pitfalls), but it’s definitely less likely for them to display the page correctly than if it were valid. Often, invalid pages will cause the browser to render in “Quirks Mode” which often affects overall spacing layout, and not just in the invalid part of the page! Search engines can also run into stumbling points in non-valid pages, which may keep you from ranking where you should in the search engine results pages.

Fortunately, creating valid pages is fairly easy and there are a number of helpful tools to help you get the work done.

Here is a list of the common pitfalls that we see:

  • All tags must ether have a closing tag (p then /p) or be self-closing (br/).
  • Images must have an alt tag, even if it is an empty one (it is a required attribute).
  • All tags should be lower case (“img” rather than “IMG”).

All sites produced by Coalmarch Productions, LLC. are in some type of XHTML (typically 1.0 and either Strict or Transitional). This adds a few extra things for you to watch for that might not have mattered in the past, most often self-closing break tags. If you use an application like DreamWeaver to generate HTML for you to use directly in pages, configure your program to output XHTML.