What is W3C? Are W3C Errors Relevant to SEO?

SMS Text

A very well compiled thread at WebproWorld discusses what W3C is and why it is so important to conform to its standards.

W3C refers to the World Wide Web Consortium working to develop open standards for the World Wide Web (abbreviated WWW or W3) so that Web documents can be consistently displayed across all platforms.

Founded in 1994 the consortium is still the main web standard against which all websites are evaluated. The most well known W3C tool is Markup Validation Service that checks the markup validity of Web documents in HTML, XHTML, SMIL, MathML, etc. Other valuable tools include RSS/Atom feed validator or CSS validator, Mobile content checker, and broken link checker.

The benefits of conforming to W3C standards include:

  • Search Engine Visibility (related discussions);
  • Browser Compatibility (including voice browsers, Braille browsers or hand-held browsers, screen readers, etc).
  • Time-saving;
  • Convertibility (W3C compliant documents can be easily converted to other formats including database and word document.);
  • Stability (W3C codes ensure both forward and backward compatibility which helps the data written in old standard to work in newer browsers.);
  • Universality (W3C standards-compliant coding ensures that each developer easily understand the existing coding conventions and the new designers also pick up where their predecessors left off.)

Still, the criticism in webmaster and SEO communities does take place:

  • many of the standards are too old and are based on the last century realia (e.g. according to W3C any page limit is twenty kilobytes which is not necessary to conform to with today’s high-speed Internet connections);
  • the market is moving many times faster than the W3C committee (e.g. mobile Internet which evolves too fast for both W3C and Google to compile);
  • some of W3C tools are often broken or too slow which is unacceptable when speaking about the committee aiming at standardized www;
  • standards have a tendency to “stifle creativity, never allowing web developers to push the boundaries of what is acceptable in order to see what might be accomplished outside the rules.

So my main question is: is checking a website against W3C validity part of your on-site diagnostics? Do you still care? Do you pay attention to all errors or only to to major ones (skipping what you deem unimportant)?

Ann Smarty

Ann Smarty

Brand amd Community Manager at Internet Marketing Ninjas
Ann Smarty is the blogger and community manager at Internet Marketing Ninjas. Ann's expertise in blogging and tools serve as a base for her writing,... Read Full Bio
Ann Smarty
Get the latest news from Search Engine Journal!
We value your privacy! See our policy here.
  • “according to W3C any page limit is twenty kilobytes which is not necessary to conform to with today’s high-speed Internet connections”

    A very large percentage of users DO NOT have broadband at home (45%). Sure, 20kb is too small, but almost one of two users will choke over 100k.

  • It was fun earlier to steal link juice from w3c lists … getting your site to pagerank 7 or 8 without much effort but it does not work any more … pity for all that linkjuice wasted at w3c.
    Ann as usual your article rocks and it is very smart, ahead of curve… and if I would not be married I would try to date you.

  • I just wrote about this in my blog, so I’m curious to see what people will say.

    In my opinion, W3C validation and SEO aren’t very closely related. Sure, W3C validation is important and everyone should try to have code as clean and validated as possible. However, a site with minimum code bloat, crawl-able code and relevant content will compete at the same level with its replica for a page validated with no errors. W3C should be emphasized by web developers, to ensure usability amongst different browsers and maximum “code cleanliness”, but when it comes to SEO it’s not a pending factor.

    ps: heck, check searchenginejournal.com’s validation – many errors, some warnings, but you guys seem to be doing ok with your SEO 😉

  • I don’t use the w3c validator but I do find that using some of the old html based standards makes things easier for bots to crawl.

  • I use W3C validation to make sure that the user experience isn’t going to be a bad one. There are people out there who use outdated browsers (IE6 for example), and if the page does not render well for those people, you may not get them back.

    It may not be a big part of SEO, but I still consider user experience a high priority when I am building and optimizing sites. You can have the best SERP on the web, but if the user’s browser won’t render your site properly, what’s the use?

  • ..oh, so it a nutshell (I forgot to add this to my comment above):

    Developers should definitely be aware of standards.

    SEOs should understand them but not place a lot of focus.

  • W3C compliance in no way affects search engine visibility — not where the major search engines are concerned.

    This is an easy topic to get burned on, and probably most people in the SEO community who have discussed it HAVE been burned for it.

    There is no direct correlation with or benefit for SEO in adhering to W3C compliance, which only extends to a subset of documents that SEOs have to work with anyway.

    I DO recommend W3C compliance for accessibility and because standards are a good thing in general, but we’re going to be working with non-HTML documents and non-W3C compliant HTML documents for years to come.

  • No matter if W3C compliance affects or not search engine visibility, I recommend to avoid promoting the idea that valid HTML is a useless practice. Otherwise the web industry will never ever recover from the incompetence it already has to deal with.

    In addition I wanted to mention here that I upgraded my web site doctype to XHTML+RDFa, and diverse browsers have problems with just one single markup error. I am wondering how bots would deal with that. Any thoughts?

  • “According to W3C any page limit is twenty kilobytes…”


  • If a site validates to the strictest of W3C validation, it is semantically correct. It’s been proven that the SEs prefer a semantically written page. It relays the information faster, cleaner, and easier to read. I’ve done testing myself on websites with identical content, one W3C valid and one not. The W3C valid site placed higher every time. In a competitive keyword situation I know my W3C valid site has a better chance at the top spot.

  • Ann,

    This is a good questions. Personally I am the kind of person that wants my site or sites to validate regardless. I just can’t stand the idea of there being an error even if the average person can’t see it.

    However my experience has shown me that most minor validation error have little impact on search ranking or SEO in general.

  • Mike S,

    it is not true that if a a site validates to the strictest of W3C validation is semantically correct.

    If you don’t follow semantic markup your pages can still validate, because the W3C or other validators cannot know if you’ve used other tags to fake your headings or not, for example.

    Therefore semantics and standards aren’t necessarily the same.

    Although, using semantic markup is recommended, because you will have the following benefits:

    1. Longevity;
    2. Search engines rank keyword weight based on semantic structure;
    3. Your markup will make sense to anyone else, whether today or later.

    Upon the chance I would like to share an interesting interview about Semantic Technologies with Matt Cutts: http://www.readwriteweb.com/archives/interview_with_matt_cutts_next_generation_search.php

  • “It’s been proven that the SEs prefer a semantically written page … ”

    Proven heh? … I’d like to see the proof … I know for a fact 18 nationally ranking web sites that were all written in spaghetti code by many different developers … However, every one of these sites are to this day number one for lot’s of keywords …

    I know that sites rank without validation because I was the person pushing to have the sites updated … the fact is … the company had no reason to update them … they ranked …

    Though I am a strong advocate of standards compliance and support validation for usability …

    As far as search engines ‘preferring’ sites that validate … that’s an interesting one … have you ever seen a web site in Lynx? …

    Let’s go to Minnesota on this … Show Me The Proof …


  • Mike …

    BTW … 🙂

    Since your a standards guru … you might want to double check your own first …


  • I think that validation is absolutely a part of SEO. It’s certainly not going to make or break you, but it’s just another one of the thousands of variables that affect organic optimization.

    It’s the little things working together and playing off of each other that make up the most successful sites.

    I recently wrote about how the foundation and architecture of a site is important for SEO: http://levit.me/2008/search-engine-optimize/how-an-automobile-is-much-like-a-website-and-how-it-affects-seo/

  • Florida_SEO,

    I think you must double check yourself before posting garbage about standards advocates.

    Mike is using CSS 3 and validates: http://jigsaw.w3.org/css-validator/validator?uri=http%3A%2F%2Fwww.scowers.com%2Fwp-content%2Fthemes%2Fblue-mist%2Fstyle.css&profile=css3&usermedium=all&warning=1&lang=en

  • @John …

    Yes you’re right … I stand corrected … 🙂

  • Florida_SEO are you serious asking Mike S for a proof that the SEs prefer a semantically written pages? Or were you just kidding?

  • Honestly, I was just debating his argument …

    I don’t see that there is substantive proof to his statements. However, I’ll jump off the soap box now …

    Good article Ann … you sure fired up a spin (Sphinn) story with this one 🙂

  • Florida_SEO you were debating the argument of Mike S that SE give weight to semantical markup elements like …, ,,,,, etc?


  • Semantical elements: h1-h6, b, i, strong, em, dt, etc.

  • I was Not debating on semantic elements …

    I was debating on the subject of validation being a proven factor in rankings …

    The argument was supported in his statement …

    “In a competitive keyword situation I know my W3C valid site has a better chance at the top spot.” …

    That’s simply not true … Rankings are based on authority and relevance … not compliance and standards …

    That’s all.

  • Did he say “In a competitive keyword situation I know my W3C valid site has a better chance at the top spot.” ?

    Well then I think he did not pose the issue properly. He should have probably said:

    “In a competitive keyword situation I know my marked up correctly site has a better chance at the top spot. That means I use headings correctly, utilize at least the h1, h2 and h3 tags and I make sure the content of each is related in the semantic outline.”

    Would you like that?

  • “Would you like that? … ”

    This is getting immature … thanks ..

  • What do you mean with immature? Just tell if you agree or not?

  • Be certain that you have structured themes in your content, and that you include a supporting cast of semantically connected keywords. Reference Google’s patent number 7,249,121 — Identification of semantic units from within a search query: http://patft1.uspto.gov/netacgi/nph-Parser?Sect1=PTO2&Sect2=HITOFF&p=1&u=%2Fnetahtml%2FPTO%2Fsearch-bool.html&r=1&f=G&l=50&co1=AND&d=PTXT&s1=7,249,121.PN.&OS=PN/7,249,121&RS=PN/7,249,121

    I hope this post is not getting immature.

  • The comment “Would you like that? ” … Smacked of facetiousness and sarcasm at best …

    The above referenced article is referencing factors that have nothing to do with search engine’s preferring w3C validation …

    What I believe you are attempting to qualify as substantive evidence … is confusing …

    The patent article is related to LSI … How does that correlate w3C validation?

    As the claim to the document states,

    “identifying documents relating to the query by comparing search terms in the query to an index of a corpus”

    Unless I am mistaken … that patent is regarding latent semantic indexing …

    Thanks …

  • Florida_S I might smacked of facetiousness and sarcasm at best …, but that because you drawed the web site of a poster here to prove that he is wrong about something. And that is not nice practice. As you see I did not draw your site into this thread telling what you might doing very wrong. (If you think you would like to bring my site into this discussion, I definitely won’t have a problem with that).

    Also, I am not attempting to qualify as substantive evidence, since if I am not talking in my last posts about W3C markup validation.

    Once again:
    “In a competitive keyword situation I know my marked up correctly site has a better chance at the top spot. That means I use headings correctly, utilize at least the h1, h2 and h3 tags and I make sure the content of each is related in the semantic outline.”

    Marked up correctly, does not mean valid markup.

    I will give you an example of an incorrect marked up or of a not semantically outlined page:

    1. A page has “h2” headings, and does not have an “h1” tag.

    2. The markup of the footer of a page comes first after the “body” tag or somewhere close to the top, instead of being the last markup of the page.

  • We are discussing two totally different things here …

    I ~ w3C Validation » Rankings
    You ~ Semantic Markup » Rankings

    I’ll exit the stage now …

    Best regards,

  • I do agree with most of the points, but I still like the idea that there is an organization setting some standards…

  • Its rather simple in my book.

    Validated code is a benefit for many reasons. With hundreds of factors determining your rankings, this is most likely one of them. It probably has a very small impact, but is a factor none the less. Why disregard any factor that could effect rankings, especially in competitive markets. Not to mention gaining all those other benefits of validated code.

    Those other sites mentioned that have spaghetti code and still rank well, I am willing to bet that other algo factors are overriding the crappy code. Again, I doubt validation has a rather large impact on rankings unless most of the other factors are rather equal.

    There are many others aspects of code on a site that have more of an impact than validation, but why in the world would you not make sure it was not an issue, just in case it became a factor.

    Many times its a company’s decision not to fix, based on financial, time or resource requirements. This is completely understandable and I would not aggressively push to have it fixed in that case. However, I would always make sure they understood the potential issues related to that decision.

    @Edward: Sorry buddy, I cant buy the argument: I know it’s wrong, but I wont fix until someone proves it wrong. Give me a call when you get a chance.

  • I am relatively new in the field of SEO, so I do lots of research on different topics. I have seen lots of websites rank well, without W3C validation. There are also a lot number of sites with lots of html errors. So, I think now a days, site owners don’t emphasize much on W3C Recommendations.

  • another wonderful posting, love them deeply.

  • Thanks a lot …. this will really be very helpful and the matter of the fact is the whole content fall so smoothly at place …. make it very readable …. appreciate the effort.

  • Thank you so much for the explanation.. wonderful sharing..keep it up pal..

  • the information is very educative and very precise. I must appreciate. The standards are always good to follow and this is in the interest of professionals as well clients.
    syed Ali
    leading- solutions interface