What is HTML validation?
How to validate and fix HTML errors and warnings?
W3C Markup Validation Service is a website that will validate HTML and compile a list of errors and warnings. Simply enter a website address on W3C and press check. After W3C code analyses is complete a detailed list will be displayed that identifies any problems within the HTML. Once they have been identified it’s a matter of finding the occurrence within the website. This can be achieved by viewing the source code via the menu options of a web browser. Using command or control F is a great way for searching within the webpage HTML. Once the mark up validation problems are located it is then possible to find solutions to fix them within the HTML via the CMS.
How does HTML validation affect SEO?
At this stage in search engine optimisation, HTML errors and warnings may not directly affect SEO performance scores or search engine placements. Some time in the future top search engines could bring out a new algorithm to test HTML and make use of these metrics. So why is it relevant now? Mark up validation can affect other factors within a site such as the usability or website page loading speed, especially on mobile devices this could indirectly affect the SEO scores and search positions. It’s also important to note that if the HTML is broken then search engines may find it hard to pick up the structured data needed for rich snippets in the search results. A large number of errors or completely broken HTML could also cause problems when rendering webpages on newer mobile devices. Though it’s rare that a website will have a 100 percent clean and valid HTML. It’s still a good idea to fix up the HTML and having clean validation may help to improve the usability and provide a higher quality user experience. Validating the HTML is also a great way to help diagnose any underlying issues within a site and this should not be over looked when creating a professional site that you could expect to find on the first page of the search results.