Do you validate your email markup before you send? This is something I don't normally do and, after seeing someone else in the community recommend it, I experimented by sending one of my emails through the w3C validator. There were lots of "errors" that, in my opinion, weren't really errors and don't appear to cause any problems - for example:

  • It complained that some attribute values (e.g. <img width=300 ...>) didn't have quotes
  • It complained that I didn't close <br> and <img> tags
  • It complained that some unexpected attributes (e.g. bgcolor) were encountered

In my experience these are non-issues -- excluding unnecessary quotes and forward slashes is common and helps reduce the overall size of the email. Many of the unexpected attributes are important fallbacks to support graceful degradation on older email clients.

So, my questions are:

  • Do you validate and, if so, why? Do you have any war stories where validation solved a problem for you?

  • Do you ignore these types of warnings or is it considered best practice to close self-closing tags and put quotes around all of your attributes?