The practiced process of search engine optimization holds a different definition to each within the field. Growing in importance however, is what should be seen as the final step in any search engine optimization campaign. That final process is the validation of HTML code to the W3C standards.

Common Sources of HTML Errors

Working on a web site and posting updates to that site often happens in minutes. With time-sensitivity so important, many designers (or those implementing the HTML changes) use a visual HTML editor to make their changes.

Once the site looks acceptable, they save it and upload it.

That is the single most common misconception about validating HTML code. Just because something looks to be correct, does not mean that it is. This is especially true when using "WYSIWYG" HTML Editors such as Macromedia's Dreamweaver, a common tool used by many.

WYSIWYG editors render HTML changes on the fly, giving the web designer an instant view of their changes. Often, this "on the-fly" process also involves adding in useless or incorrect tags - and therefore increase the amount of coding used to render that one page.

If you are optimizing or simply editing a web site with a WYSIWYG editor, take a look at the changes in HTML code both before and after your work appears to be done. Often, you will find redundant tags - or worse yet - un-validated HTML.

Getting around this is quite simple, and through practice can become second-nature. Whenever you are ready to upload a web site, validate the code through a tried-and-true HTML validation application.

If you are unsure of where to get a HTML validator, you can use web sites like, or employ the use of the W3C's services online at

When is the Time Right to Validate?

Time is always short when you work with the Internet, or so it seems. Because of that, you may be skeptical to try out anything that may absorb more of your time. Having said that, do not waste your time validating every page's code each time you make one single change.

Do however, be sure to validate the code BEFORE the web site goes online. That way, users' browsers as well as search engine spiders will be able to understand the HTML coding that you are using.

What Other Benefits Exist to Validating?

There is a lot more value to validating code than to make file sizes smaller and more easily understood. Search engines are constantly rewarding web sites that utilize clean and validated HTML. Beyond that, you are decreasing the likelihood of having users experience problems when viewing your web site.

And perhaps more importantly than anything else, you will begin to learn how to spot and avoid common sources of un-validated HTML.
September 9, 2002

Eric Lander is currently working as an executive manager at The First Listings Marketing Group, an SEO firm located in Taunton Massachusetts. With over 8 years of professional optimization experience, Eric continues to focus his work on client based optimization and educating them on search related marketing. For more information on Eric, please see his professional blog at

Search Engine Guide > Eric Lander > HTML Validation: The Final Step in Search Engine Optimization