HTML Validators: The Key to Success

6 min readSep 6, 2022

HTML validators are an essential part of building a website. Writing valid code helps ensure that your site is viewed precisely how you want it by the user. Incorrectly written HTML will cause various errors and issues with the site, and validation helps to prevent this. Valid code is much easier to view while using a screen reader and assisting various visitors with disabilities. Additionally, writing valid HTML helps with SEO and helps to drive traffic to your site. Search algorithms read the validated HTML for context while searching for their user base. If your code is written in valid HTML 5, it will be more likely to receive attention. Writing Semantic HTML that passes validation is the key to success in web development.

Invalid Code

First and foremost, unvalidated code will most likely not look correct on the page. Tags may be misread, or other browser errors may occur in which the user will not receive the information on the web page as intended. By validating your code, you can be sure that the user is seeing exactly what you want them to see. If you have ever had links or buttons that didn’t work or tables that loaded improperly, you have been the victim of invalid code.


Everybody has heard jokes about Microsoft’s Internet Explorer(IE), but how will your website react to a user loading it on Safari, the browser made by Apple? There are more browsers available now than ever, and each has its own rules and ways of interpreting web pages. HTML validation ensures that your website will be viewed as intended by the user, regardless of the browsing platform from which they choose to view it. With at least seven major browser platforms and countless other minor platforms, having validated code ensures that you have the widest net to access the most extensive user base. Failure to validate may leave your users frustrated and pointed elsewhere for their business needs.

Website Ranking & Best Practices

One of the most critical ways HTML validation will help you is through Search Engine Optimization (SEO). SEO is the make or break for many websites and companies on the internet. Every search platform, such as Google or Duck Duck go, uses “Web Crawlers” to assess websites. This “Web Crawler” will traverse any publicly accessible site and measure the HTML content. It has internal ranking metrics that it applies to sites regarding their relevance to specific search terms. If the HTML on your page is invalid, the web crawler may rank your site lower. If the HTML contains an error, it may remove your website from its indices entirely! The best way to stay on top of the search game is by making sure every addition to the website is validated.

HTML validation helps teach beginning coders the best protocols for coding. While experienced coders may naturally write code that aligns with the best web development practices, beginners often write code-filled errors. Validation is a way for newer users to correct their mistakes and write code that is better syntactically and visually. The best practice when using a validator is to validate the HTML as you develop the site constantly. This allows the coder to catch any errors before they hit live service and affect your user base.


Have you ever had a slow webpage? A website where half of it loaded instantly, but you had to load the other half for over a minute? Slow web pages can be the result of errors due to invalid HTML. Dynamic pages, content, and scripts can create formatting errors that increase load times.

Web pages that are slow to load cause user frustration and oftentimes lead to the user looking elsewhere for their needs, much to the site owner’s dismay. A website that takes over 3 seconds to load is abandoned 53% of the time. Faster load times will rank your site higher with SEO as well. 52 percent of online shoppers stated that quick page loading is critical to their site loyalty.

Retail and travel sites — 79 percent of online shoppers who experience a dissatisfying visit are less likely to buy from that site again. 64 percent would simply purchase from another online store.

The next time this happens, try using the browser development tools to look at the console. You can see firsthand the large number of errors that occur, slowing down the webpage.


In 1990, the Americans with Disabilities Act(ADA) was passed. The ADA requires that all businesses make reasonable accommodations to allow disabled people to access their businesses. You can see a nationwide change due to this law, with wheelchair access ramps on the outside of every public-facing business. Some users of websites are disabled. They must use a screen reader to view web pages to access the internet and its information. A webpage that is not validated will likely not be viewable by the screen reader. As a result, you may be infringing against disabled persons. To comply with disability laws and prevent lawsuits, validation must be used to ensure accessibility.

In 2006, Target was sued by the National Federation for the Blind. The outcome of this case had great importance, as it set a precedent for how online accessibility would be treated. This was just 1 of many in a string of high-profile websites sued for inaccessibility. In 2017 Nike was sued for failing to “design, construct, maintain, and operate its website to be fully accessible to and independently usable to blind or visually-impaired people.” Making your website accessible helps these users have a more meaningful visit. Additionally, you gain access to users that may have their needs unmet elsewhere.


Currently, web development focuses on three main viewing modes, Desktop, Mobile, and Tablet. Designing a website that handles all three viewing modes can only be done with validated HTML to prevent errors and delays. Having a website accessible by users on any of their preferred devices is only possible through HTML validation. Trying to design a website that only services desktop viewing would reject over 50% of web traffic — a sure recipe for failure.

Mobile devices have taken over browsing. While some users remain on PC, most internet usage has shifted to mobile. On Feb 22, 2022, J. Clement of statista published findings that claimed 54.4% of global web traffic consisted of mobile devices(excluding tablets). The author claims that mobile traffic began hovering around 50% of the global in 2017 before finally surpassing it in 2020 with the rise of the Covid-19 pandemic. In 2018, a company announced it would be introducing a phone with a foldable screen. As we progress forward in time, the trend is clear that devices of all shapes will be used for viewing the internet and the sites that come with it. HTML validation will be more relevant than ever as new devices with different operating requirements are introduced into the market.

Scalability on new devices

Validation will also help us when new devices are implemented that require different viewing specifications. In May 2014, Google attempted to market the “Google Glass”. Although it failed to take off at the time, the idea is still going strong. Had Google glass taken off in 2014. With all of the validation and errors that it entails. Going forward, with whatever technology the pioneers of time throw at us, it will be easier to manage with validation.

Maintenance & Website Design

Another aspect of validation that is often overlooked is its effect on maintenance and new development. Validated web pages are almost always easy to edit and can be changed or duplicated to make future web pages easier to create. Starting with a nice neat codebase makes long-term work much easier. Like a blueprint, it can be reworked once something has been validated.

Websites are a piece of digital real estate for the business. But just like tangible real estate, websites have a value associated with their location on the web. Consider the case of Uzi Nissan, which owned Uzi was sued in a lawsuit by the Nissan Motor company over the name of his website. The result was a 10-year legal battle that cost him over 3 million dollars. In the same way, you wouldn't leave the front of business unkempt, inaccessible to disabled persons, or flat out just missing; You would not leave your digital front of business unkempt, inaccessible, or missing. HTML validation has become a core component of web development because it allows the business owner to maintain their digital image with as much care as their physical image.


Validation has improved the internet for the better. It improves browsing user experiences; it reduces load times. It helps users find better results through SEO. Users experience better, more dynamic web pages because they have been validated in their creation. Web users can experience the web with whatever platform seamlessly or device they choose. It has integrated disabled persons into our society more than any previous technology. Validation improves our lives because it improves the internet so vastly.




A Seattle web design and online marketing agency that delivers high-end websites. A passion for web development and SEO.