SEO Question: What Is W3C Compliance?

I’ve been told that my website isn’t W3C Compliant. What is W3C Compliance and how can I check and make the necessary changes?

Deeho Says:

W3C compliance is a set of criteria for your HTML & CSS which ensures that your code is presented to a uniform specification as laid out by the world wide web consortium (W3C).

Tools such as will show you all errors found on each of your pages, highlighting what needs to be fixed in order for your page to validate.

Validated pages perform better in search and load faster. If you have serious validation errors then your site might throw errors, for example if a script isn’t closed correctly, it won’t load to completion, causing problems for users.

Google likes to see validated pages. Validation is a strong indicator of a well managed website.

While it can be time consuming to validate all the pages of your website, it is well worth the time and effort because of the benefits to you and your users.

W3C Compliance demonstrates that your site provides access for disabled users, access across all browsers and users on any device, as well as reducing required coding, to keep load speed down and ease site navigation.

Moving forwards, usability and accessibility (two metrics currently in use by search engines) will only increase in value, giving W3C compliant websites an advantage over non compliant sites.

Our advice is always to build and develop for the long term so optimizing the HTML & CSS code on your site is an investment in your websites future.

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