WCAG 2.1 | Validator, Checklist, and Live Human Testing

wcag 2.0 compliance

If you want your website to be accessible, you need to take a few steps to make certain that everything works properly and is usable for everyone. Using a validator is a good step, but it doesn’t work in 100% of scenarios. A checklist can be excellent, but might still leave you missing something. The best method by far is to use a combination of “Go Live” checks before launching and after every update.

At the end of the day, you should use a validator, checklist, and human testing to make sure that you’ve included everything to maintain compliance.

If you intend to put out a welcome mat for potential customers and clients with disabilities online, you probably realize that it’s essential to offer a fully accessible digital experience.

The most universally accepted and up-to-date guidelines for web accessibility today are the Web Content Accessibility Guidelines is WCAG 2.1, which includes everything in the 2.0 guidelines with additional provisions to meet newer technology.

If you’re concerned about meeting all the compliance needs, the first step is to develop a strategy to assess your current website as it compares to the regulatory needs. Then you’ll want to make a comprehensive list of any changes you need to make to maintain compliance. All of these upgrades will need to be tested to make certain that they meet standards and are easy for your users to navigate.

There are three methods we recommend using to check your website: an automated WCAG validator, a checklist, and human testing. All of these methods have benefits and limitations, which is why we recommend using more than one.

Automated WCAG Validators: Fast, But Not Fail-Safe

A WCAG validator is automatic. It can check a specific feature of a website, test whether it meets a pre-set condition, and rate it as a “pass” or a “fail.” Typically, you’ll receive an error report along with the reasons why the WCAG validation failed.

There are dozens of web accessibility testing tools such as AChecker that can automatically test whether elements of your website are WCAG compliant.¹ Some may also do a Section 508 check to ensure compliance with other laws.

For example, the World Wide Web Consortium (W3C), the international organization behind the Web Content Accessibility Guidelines, provides a program called Unicorn. This WCAG validator allows you to enter the URL of any web page, get a detailed account outlining where it isn’t WCAG compliant, and learn how you can improve the accessibility of the page.²

It’s important that PDFs and other documents also be made accessible. There is even an accessibility checker in Microsoft Word, Excel, and PowerPoint that helps flag potential accessibility issues in your documents, spreadsheets, and presentations.

The W3C also maintains a helpful searchable database, the Web Accessibility Evaluation Tools List, listing all kinds of other WCAG validators from different organizations. Some are online color and contrast checkers, and some are downloadable programs.

Tools like these are often free, and unlike a WCAG checklist, they work instantly. However, some tools only test the accessibility of one website component or type of technology.

Let’s use images on a website as an example. The law requires that images that aren’t decorative have an alternative attribute that is meaningful to the image. An automated tool will only detect the presence of the alt-text, but it will not be able to determine whether it’s relevant to the image itself. This requires manual testing. More on that below.

Something else to keep in mind is that while these WCAG validator tools are useful for giving you an idea of the level of accessibility problems with your website, you should not depend on them to provide you with a complete list of every single WCAG violation.

In short, validation tools are useful because they’re instantaneous. They automatically check the website or document and give you a full report of issues that you might need to examine or change. But like other AI, they’re not foolproof. They can false flag things that are not problematic and miss things that should be changed to meet compliance.

WCAG 2.1 Checklists: Easy, But Not Exhaustive

A WCAG checklist is a simple, easy-to-follow, systematic list of web accessibility requirements, or “success criteria” for WCAG compliance.

If you happen to find the full set of Web Content Accessibility Guidelines intimidating or filled with jargon you don’t understand, you might find it more straightforward to follow a simple website accessibility checklist to ensure you have a few basic accessible features in place. Download our Must Have WCAG 2.1 Checklist here.

For example, using a checklist, you might be guided to look at whether the text on your web page will still be formatted properly and visible when a user enlarges it. Thus, a WCAG checklist can be an extremely useful and informative reference. But, like the validator, you should know that the checklist is not an exhaustive method. There’s a margin of error with the checklist method.

Your website might meet all the requirements in the list, but that’s in no way a guarantee that there aren’t still major accessibility problems with the site. However, a web accessibility-testing checklist will help you find many of the most obvious barriers.

Human Testing for WCAG Compliance

Nothing beats web accessibility testing with real human beings, especially if they have disabilities. It’s only this kind of evaluation that will uncover usability problems that can’t be identified using automatic validators or by following checklists.

This process is important because you get real world feedback. Checking your website yourself can be difficult. You already know where everything is and what it looks like. You designed it, so it’s difficult to really determine how it works. Add the layer that you’re improving it for people with disabilities and it becomes even more impossible to truly understand a visitor’s experience with the site.

Having your site tested by people who are not familiar with the website and those who have the disabilities that make accessibility an issue can help you pinpoint things that are bothersome to them. These can often be things you wouldn’t think of yourself and might not be flagged through an automatic validator or your handy dandy checklist.
“Getting the right people and skills involved makes your accessibility evaluations more effective.”³

For example, you’ll learn more about the way a person with a certain disability might use assistive technology, and what they’re bumping against when they try to use that technology to visit your website.

A professional consultant will involve a team of experienced human evaluators with a range of disabilities and technologies. They’ll look at all critical aspects of your website, not just a handful, and they’ll have the best chance at catching usability glitches. They’ll also offer you valuable and practical WCAG 2.1 accessibility remediation solutions, regardless of which level of compliance you’re aiming for — whether you’re going for WCAG AAA status or not.

When you use a WCAG validator, a WCAG checklist, human evaluation or a combination of all three, you’re taking important steps to ensure that people with disabilities have an enhanced online experience when they turn to your website for information, products or services. Incidentally, you’re also complying with laws such as the Americans with Disabilities Act (ADA), which protects people with disabilities from discrimination and barriers, including online barriers.4,5

Many regulations, like the refreshed Section 508 and the Air Carrier Access Act (ACAA), use the WCAG 2.1 guidelines and the technical requirements for web accessibility. Adhering to them allows organizations to achieve and maintain compliance with required standards and regulations.

Best of all, making your website WCAG 2.1 compliant means you’re also benefiting many other groups. These include people who are older, people who are inexperienced with the Internet, folks who are less fluent in English, and anyone using mobile technologies. In other words, offering an accessible website means putting out a welcome mat for everyone.

Does your website meet all the requirements to make your truly accessible for every visitor? Find out by requesting a personalized demo from the experts at eSSENTIAL Accessibility.


  1. AChecker.ca
  2. Unicorn – WSC’s Unified Validator
  3. Evaluating Web Accessibility Overview, W3C
  4. ADA Update: A Primer for State and Local Governments, ADA.gov
  5. A Guide to Disability Rights Laws, ADA.gov

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