Creating W3C valid websites should be the goal of every Web technician. Valid websites are consistent across browsers, forward compatible, and cleanly presented to both spiders and accessibility programs such as text-to-speech readers (the latter being a legal requirement in the UK). Valid sites are also less likely to break in mobile devices due to quirks of the particular mobile browser. The question many people are asking, however, is whether valid code matters to search engine rankings.
Currently, Google does not seem to factor W3C valid code directly into its ranking algorithm; even Google’s pages themselves are not 100 percent valid. However, some speculate that this may change in the future as Google continually looks for more ways to determine a site’s credibility. When it comes to changes in the algorithm, it never hurts to be prepared.
Although validation itself does not appear to be an algorithmic factor, it can still affect a page’s rankings in indirect ways. Perhaps the most critical of these is that, while the majority of validation errors are not deadly, some can cause a site to be misunderstood or even skipped entirely by search engine robots. These dangerous errors can include incorrect doctype declaration, unescaped entities, and improperly closed HTML tags.
If a site is not skipped over completely, invalid code still has less of a chance to be understood in its proper context. Semantic design is becoming more important as search engine algorithms grow in intelligence. Take as one example Google Squared, Google’s newest attempt at intelligently displaying search result information. Rather than simply displaying pages matching keywords in a long list, the engine crawls pages to pull information suitable for display in a tabular format. Even for traditional search engines, however, more easily understood content has a greater likelihood of appearing in organic results.
W3C validation also encourages the proper use of tags like image alt attributes. Running a validation check on a site will quickly reveal omissions of these tags. Since using them properly can be important to SEO, this is one case when being W3C compliant could have a direct positive effect on rankings.
There are many arguments for creating W3C valid websites that have nothing to do with SEO, but there are also plenty of strictly SEO reasons to comply with current Web standards. While W3C invalid sites will not be immediately booted from major search engines, avoiding errors in coding can prevent errors in crawling, allow more intelligent indexing, and cause more of a site’s actual content to be indexed. When giving such care to every other detail of a site, it only makes sense for the SEO to pay attention to validation standards as well.
Tags: SEO, validation, w3c
