Is W3C Compliance Important For SEO?

On Friday Michael Gray answered the question of whether or not W3c compliance and accessibility can impact your optimization. I agree with everything Michael said, but wanted to add a few more points.

According to Michael

From my experience having a site that is 100% code compliant doesn’t give you any SEO benefit. That said throwing up a page with complete disregard for valid code is looking for trouble.

My view exactly. Search engines are interested in your content. They want to present the most relevant results they can to a search query. If that content happens to be on a page that doesn’t validate it’s still the most relevant. If you need proof do a search and check the top results for how well they validate. My guess is that in most cases the pages won’t completely validate. You can also check the pages of the search engines themselves. Last time I looked none of them validated.

However, if your code is so poor it can have a negative impact on seo. The most obvious example is having unspiderable navigation, but it’s not the only issue. Poor code builds dams that impedes the flow of search traffic into your site. Validating your site can catch many of those errors.

Writing Valid Code Is Easier Than You Think

Does your site need to be 100% compliant? Probably not when it comes to seo, but the majority are validation errors are very easy easy to fix. Often a large number of validation errors are the result of just a few coding mistakes. I’ve found that fixing the few obvious things like forgetting to close a tag, or the lack of an alt attribute on images, cleans up most validation errors.

Contrary to what you often hear making a site 100% compliant isn’t hard either. See what’s reported as being in error and do a few searches and you can find the solution. Sure it will take a little time to find the solution and implement the fix the first time you encounter it, but once you’ve figured it out it’s easy to incorporate the next time. If you plan on developing sites you should understand why something doesn’t validate and how to correct it.

It can be difficult to validate some 3rd party applications unless you’re familiar with the code or you’re willing to put in the time to learn it, but as long as you have a desire to understand how to write compliant and accessible code there’s little excuse not to get your own code to validate.

Coding To Standards Makes Cross Browser Development Easier

As a developer I can tell you it’s much easier to code a site to standards and then tweak things for various browsers. Mostly that tweaking will be solely for Internet Explorer and if you make use of conditional comments you can even get your IE hacks to validate. Not everyone uses one browser. Remember that traffic is meaningless if it has trouble viewing your pages.

An accessible site is one that renders well in as many devices as possible and the best way to achieve that is to write valid and accessible code. I can’t tell you how many sites I’ve never gotten beyond a single page because it didn’t display well in Firefox. If you can’t be bothered to develop a site that works in the second most popular browser why should I think you’ll be bothered to resolve any issues that may come up with your products or services.

Most importantly writing accessible code is just the right thing to do.

And even if you won’t see any ranking benefit at the moment you may at some point. Accessible search has been available through Google labs since last summer and sites that validate for W3C compliance and accessibility absolutely do receive a ranking boost in it. Perhaps one day the algorithm giving that boost will find it’s way into Google’s general search engine.

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  1. I’ve noticed the same thing about validation errors generally predicting which pages are going to work on some browsers and not others. You need to go a little bit further if you’re using png files, but for simple mistakes ( like [script src=”x” /] or [?a] instead of [/a] ) it’s much, much easier to learn as soon as possible that you made a typo that needs to be fixed. The missing alt attribute report is as handy as it is important, too.

  2. Absolutely. And once you go through all the typos and other obvious things I find so many of the validation errors are gone as well. One error in the code can often lead to dozens of validation errors in the report, especially if the error is a closing tag.

  3. This is one of those cases where there are actually benefits, but they’re a little harder to see.

    For example, the dam situation created by poor code. Valid code = no dams = better for SEO than poor code = benefits.

    What also needs to be considered in the equation (and never is) is the possibility of organic traffic and inbound links that occur as the result of a combination of a well-coded site and unique content. Both of these elements will need to be in place (along with design, of course) in order to maximize these types of links.

    You also touched on the Accessible Search. My personal belief is that it’s only a matter of time before accessibility becomes part of the regular algorithm simply because most spammers are poor coders and it would provide an indirect means of algorithmically reducing spam. It may not be here yet, but it’s coming (at least from Big G’s standpoint.)

  4. That’s true about the inbound links. There are geeks among us who might want to look at your code before linking to you. If you’re code isn’t validating no link.

    I think at some point the accessible search will make its way into the general algorithm too. I’m not sure I agree the spammers are poor coders though. The more obvious ones are, but some of the most profitable spammers are also some of the best coders. It’s what makes them so profitable.

    I think the accessible search will eventually find its way in once the U.S. decides it should be taken more seriously. I think we’ll eventually see a certain amount of legal requirements to make a site accessible.

    I also think valid code is an indicator of quality. I can understand that search engines care about content first, but I think sites that take the little bit of extra time to meet accessibility compliance are also the sites that have put a little more into the quality of their content as well. Sooner or later search engines will make that connection too.

  5. There is also the issue of legality. It’s the website owners responsibility to ensure that their website adhere’s to acessibility laws in their country. Any webdesigner worth his salt knows that being as compliant with W3C Standards is one way of doing that, or at lest a large step towards it.

    W3C Compliance should be a given for all new websites if their coded by a professional. Personal websites may be a little more flexible, but ensuring a website is completely compliant is a good way to learn.

    • True. Depends where you live and what the laws are there, of course.

      Even if it’s not law, make your site more accessible is just the right thing to do. I know I’m not perfect with that here, but I did try to do what I knew how to do and I learn all the time how to build more accessible sites.

      I should probably write a few posts on the subject. W3C compliance is definitely a start, but there’s more.

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