Why should I care?

Future proofing your sites

At the present time (November 2006), most web browers are fairly lax about the kind of markup that they will work with. Even if your HTML fails validation with hundreds of warnings and many errors, chances are that it will render well enough.

Catching errors

Validation is a really good way of catching errors in your HTML or CSS. Think of it as compilation for web pages. Of course, you hope that any errors that you make when writing html will be immediately obvious when you preview the page in a browser. However, this is not always the case. Often an error will only manifest itself visibly if the place with the error is followed by a particular type of code. Fine if that code is already in place, more difficult if that content won't be added for a month or so.

What can I do about it?

Two easy ways to check that your HTML validates:

External links