W3C Validation: What Is It and Why Does It Matter?

By Ryan Owens

Stratatomic Custom Website Design W3C Validation

W3C Validation Is The Hallmark of a Well-Constructed Website

W3C stands for the World Wide Web Consortium, a recognized global web standards body. Tim Berners-Lee founded this organization and is run by a full-time staff to continue creating and preserving web standards.

These specifications are then used to direct the creation of code that lives up to those standards by web developers and browsers. They write the rule-book of the web, which helps determine whether our code is well-written or poorly written. Under the skin of every website is source code, which is the only thing Google and other search engines see. Therefore it's very important that this code is highly optimized and strategically built to perform in all aspects of technology.

Think about it. Would you buy a car that had dozens or even hundreds of defects that were unknown to you? Perhaps the car has nice paint, starts up on the first time, and seemingly runs just fine. But the car was "modified" by the previous owner, and soon enough those defects start showing up in unexpected places. The check engine light comes on intermittently. The ABS warning light only comes on when the temperature drops below 50°. The fuel gauge works - some of the time. But no mechanic can fix your car, because it's not OBDII compliant and therefore they can't read or troubleshoot the error codes. The previous owner used suspect parts that aren't covered by a manufacturer's warranty, and there's no instruction manual for reference.

Your website and it's underlying source code are kind of like that, but actually much more complicated. That's just the nature of technology and the internet. At Stratatomic, we firmly believe that your website should be as optimzed and perfect under the hood as it is on the outside. Just as with a car, the parts that you can't see are arguably more important that what you can see. We wouldn't sell you a car with hidden defects, and we certainly wouldn't sell you a website that had errors unbeknownst to you. Nor should you settle for one, because eventually it's going to impact you where it matters most - in your wallet. So let's understand some essential points of W3C validation and why you should care about it.

What is W3C Validation?

World Wide Web Consortium (W3C) allows internet users to check HTML and XHTML documents for well-formatted markup. Markup validation is an important step towards ensuring the technical quality of web pages.

Why Validate a Site on W3C?

W3C validation is the process of checking a website's code to determine if it follows the formatting standards. If you fail to validate your website's pages based on W3C standards, your website will most likely suffer from errors or poor traffic owing to poor formatting, readability or page load speed.

1. Improved Rankings in Search Engines

W3C validation helps you to get better rankings in search engines (SEO). Errors in your code can affect your site's performance and make a big impact on your site's SEO. Search engines check the HTML or XHTML code of your website when searching.

If they find invalid HTML or XHTML code – meaning code that does not follow the official rules, you might be penalized or even removed from their indexes. If there is an error on your web page code, robots may stop searching your entire website's content. Additionally, source code that is lean and optimized significantly affects page load speed and browser rendering and compatibility, which are factors in search engine ranking algorithms.

2. Validation Helps Teach Best Practices

Having a standards-compliant code is the best practice for web design. It also teaches and encourages best practices for web design. While many veterans have learned to create error-free code and make relatively few validation errors, most beginners make more errors. Computer validation checks can help beginners learn from their mistakes. Most all common CMS platforms such as WordPress, Drupal and Joomla! create garbage code, bloated and replete with errors and generally sloppy syntax. The code they create will never validate without a ton of work, and I've yet to meet a developer who is willing to put in that kind of effort. Of course this makes maintenance that much more difficult, and affects their page load speed and search engine performance. That is why a custom coded website will always outperform anything created by these platforms in every aspect that counts, such as Security, Design and Performance.

"These technologies, which we call "web standards," are carefully designed to deliver the greatest benefits to the greatest number of web users while ensuring the long-term viability of any document published on the web." — Web Standards Group

3. Improved Website User Experience

W3C validated websites will be easily accessed by people with modern browsers. Validation improves usability and functionality because your users are less likely to run into errors when displayed on browsers compared to non-validated websites.

Validation is fully compatible with a wide range of dynamic pages, scripting, active content, and multimedia presentations.

The website validation process allows website developers to correct formatting errors that impact website performance, and following international standards, the code used in websites is reduced in size while improving efficiency.

Because of this, web pages are displayed much faster and flow much better compared to websites that have not been validated. With Mobile optimization now being a major ranking factor in Google, having a web page that loads quickly on a mobile device is highly critical.

4. Make Websites Browser Friendly

Making websites browser friendly is one of the biggest reasons why W3C code validation was introduced. Websites that are not validated may display correctly in one browser but not in other browsers. Many websites face cross-browser problems. Just because you use one browser does not mean that your website visitors will use the same thing, or even your website the same way that you do. What you or anyone sees is certainly different than how Google and the search engines see it. The source code is the only thing that matters. This is especially critical on Mobile devices and those with an international customer base.

Websites that are not validated may display formatting problems when used in certain browsers. On the other hand, W3C validated websites are always displayed without errors regardless of what browser is used.

As of today there are five major web browsers: Google Chrome, Mozilla Firefox, Microsoft Edge, and Apple Safari. Global usage among them translates to billions of internet users scattered around the globe. Among these primary browsers are countless variations, versions and configurations, all of which affects how they interprete your website's source code. Strictly adhering to web standards is the only way to guarantee compatibility with all broswers and configurations, ensuring consistent and reliable performance on any device.

5. Multiple Device Accessibility

With the recent boom in smartphones and tablets, more people will be accessing the internet from mobile devices than desktop computers. In fact, Google uses a Mobile-first indexing and ranking system for all websites.

By 2020, mobile commerce will reach $2.91 trillion worldwide, and some sectors are seeing an even higher proportion of mobile traffic, so there is a growing need for website owners to maximize the usability of their websites on new devices.

Unfortunately, many website owners do not take advantage of this growth and forego W3C validation that makes sure their websites and web pages are mobile-friendly too. If you want your website to be visited by as many users as possible, accessibility should be a big factor.

6. Validation Makes for Easy Coding and Maintenance

Websites or web pages that validate using W3C website validation have code formatted efficiently and are easy to edit, and it helps website owners to create a new page or another new website with similar formatting. As sites grow to hundreds of pages over time, new features get added and technology keeps moving forward, having clean code makes it easy to maintain and add new functionality that doesn't break existing technologies.

The validated code used in W3C HTML validation, W3C XHTML validation, or W3C CSS validation can also be used in future sites.

7. Validation as a Debugging Tool

Validators tell you where you have errors in your code. If your page isn't displaying as expected, a validator might very well point you to the cause of the display problems.

Also, an invalid code that may display fine in one document may show stopping errors in another because of the encompassing code.

How Do You Validate Your Code?

Validation is comparing your code to W3C standards. The best way to validate your code is by using the W3C validation tools.

HTML validator
This validator checks the markup validity of web documents in HTML, XHTML, SMIL, MathML, etc.

CSS validator
This validator checks the CSS validity of web documents in HTML, XHTML etc.

There are plenty of browser extensions that will test the page you're viewing against the W3C validators.


If at all possible, any website should follow W3C validation requirements. It is the right way to do it, but it has many enduring advantages, such as extending the lifespan of the website pages, maintaining browser compatibility, search engine performance, device compliance and much more. This brief overview can help you understand why W3C is important and necessary to test all Stratatomic websites for 100% W3C validation before calling a project complete.

Stratatomic is a creative firm specializing in web, multimedia, advertising and graphic communications. Stratatomic also offers complete solutions for web site hosting, WebAdmin™ site management software, Google Analytics™ and Google WebTools™ site analysis tools, providing clients with a singular resource for top-to-bottom implementation of their internet marketing strategies. Founded in 2000 by Ryan Owens, Stratatomic LLC is a privately held company based in Greenville, SC.

For more information, contact Stratatomic at 864.271.7021 or visit the website at www.stratatomic.com.

Ryan Owens : Stratatomic Ryan Owens is the founder, president and chief creative officer of Stratatomic LLC. A graduate of the University of South Carolina, Ryan serves as design strategist and technical director for all agency projects and brings more than 30 years of industry experience. Mr. Owens presently serves as Senior UX Designer for Sync.MD, and on the Digital Marketing Advisory Board at the University of South Florida Muma College of Business, and also as an adjunct professor at Furman University, offering instruction in Logo & Symbol Design as well as Graphic & Advertising Design.