Does W3C compliance impact a site’s search rankings?

[kelvintrinity]

Well for now it does not have direct impact on google rankings as if u see google pages themselves do not validate but maybe in future google might add it in their algorithm. Besides there is much more to web then only google, yahoo, ask, msn etc. for instance digg which is a very popular social bookmarking website which provides high end traffic to its users and is the hot spot right now. many people using digg use browsers like safari, firefox opera and when the sites are made they are not checked in every browser. thus it affects the look and maybe it may even change the structure of a site in different browsers.

Validating your source code is utmost necessary for search engine optimization, why you ask?
search engine spiders and web browsers work in somewhat similar ways. Spiders “crawl” the web indexing web pages and their content. They are basically toned-down web browsers that aren’t concerned with displaying for a user but with recognizing content. In other words, search engine spiders are looking at the same code your web browser is and parsing it in a very similar way. This difference in functionality, however, is vast.

There is a very real pressure on web browser developers to ensure that their browsers display pages correctly to the user. This often includes forgiving errors in the source code. Improperly nested elements, unclosed tags, unrecognized parameters – these are all errors in HTML code that might not affect your web page’s display in your favorite browser. When it comes to search engine spiders, however, it can be an entirely different story.

That is not to say that small errors in your HTML code will spell death for your search engine rankings. Certainly they won’t normally make your page invisible to spiders.

They can, however, disrupt the vastly important process of a spider parsing your page for all relevant content or make some of that content invisible. And since so much of SEO is paying close attention to every little detail of your site and its content, why leave the possibility open of causing problems for search engines when they try to index your pages?

well validating your site can be a big headache but if you do it its a hell lot beneficial to you.

[chitra]

You have a valid point kelvin, I think complying to W3C standards is worth the effort. IMO, it is also important to make your website compatible to mobile devices because mobile internet users are growing rapidly.