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Home Accessibility / A11y Testing

Accessibility (A11y) Testing with CSS HTML Validator

Use CSS HTML Validator Home, Pro or Enterprise to help check for:

  • WCAG Accessibility Compliance
  • Section 508 issues
  • Broken links
  • Bad HTML and CSS that can cause accessibility problems
  • Other accessibility issues
  • Much more

Jump to warning about overlay products

More detailed information about what is checked can be found in these documentation pages:

⚠ Jump to warning about overlay products

CSS HTML Validator Home, Pro or Enterprise Software for Windows (or htmlval for Mac or Linux) is a desktop (as opposed to cloud-based) software tool that can be used to check web documents for issues that affect accessibility, usability, and functionality. Checks are based on WCAG 1.0, WCAG 2.0/2.1, and/or Section 508 requirements.

NOTE: Be sure to turn accessibility checking on in the Accessibility section of the Validator Engine Options (go to Options > Validator Engine Options). Read below for more information about accessibility and how CSS HTML Validator can help.

💡 Did you know? A11y is a numeronym for accessibility. The number 11 replaces the 11 letters between the first and last letters of the word 'accessibility'.

💡 Did you know? Compliance with WCAG 2.0/2.1 (at Level AA) is now the de facto baseline for government regulators, courts, advocacy groups, and private plaintiffs for determining whether a website is accessible. CSS HTML Validator can help you with compliance.

Section 508: For US government websites, CSS HTML Validator helps check for Section 508 compliance and has been purchased by many United States government organizations including the Social Security Administration, Federal Highway Administration, Centers for Disease Control, US Postal Service, Department of Agriculture, Department of Commerce, Department of Energy, Library of Congress, FDIC, NASA, NOAA, US Geological Survey, and the US Census Bureau.

Simply open your document (a CSS file or HTML file containing CSS) in the program, press F6, and your document is checked. It's that simple!

It's also easy to check a live DOM. This can be extremely useful when a page's HTML is altered with JavaScript, which is the case for many of today's modern websites.

TIP: Don't settle for an accessibility testing tool that doesn't also check the HTML and CSS syntax of the page. CSS HTML Validator checks HTML and CSS syntax in addition to checking for other accessibility issues.

⚠ WARNING: Beware of Quick-Fix Accessibility Overlay Products Like AccessiBe

Be careful when choosing to use a "quick-fix" accessibility product like an overlay. Instead, take the time to address accessibility as an integral (built-in) part of your website. Check your website with good accessibility checking tools that help you integrate accessibility natively instead of as an afterthought. See the articles below for more information.

What is Web Accessibility? ♿

When a website is accessible, it means that anyone, regardless of ability, can enjoy and use the website effectively. As an added bonus, it also makes the website more machine readable, and that often has search engine benefits. When a website is not accessible, then people with disabilities can be prevented from having similar access to a web page's information and function compared to someone without a disability. This can result in user complaints and even in lawsuits if the website is legally required to be accessible.

As a simple example, imagine a website with many images on it (using the img element). A blind visitor may be using a screen reader or talking browser to "view" this page. One of the most significant (and very easy to do) actions a web developer can do to increase accessibility and make a website more accessible is to supply appropriate alternative text for each image using the alt attribute. This "alt" text is what the user's screen reader or talking browser will read to the blind user because he or she cannot see the images. If this "alt" text is not there, then the website becomes less accessible to blind users.

Also, consider an image on a product page that says "Buy Now" but there is no alternative text for this image. Because there is no "alt" text, a blind user could easily get lost if they are trying to order the product. Instead, the image should have an alt attribute that is simply alt="Buy Now". This will let a screen reader or talking browser tell the blind user that the image is the order button, and the user will then know what to do to continue buying the product. Without this simple addition, a blind user would not be able to use the website as effectively as a user who is not disabled.

Why Would I Want to Make a Website Accessible?

There are many reasons why you should make your website accessible:

How Can CSS HTML Validator Help?

CSS HTML Validator works at the HTML and CSS level to generate messages that help you make your website more accessible. Furthermore, unlike other accessibility tools, CSS HTML Validator also generates messages about the syntax problems and errors in your HTML and CSS documents. These issues are often another source of website problems.

By utilizing CSS HTML Validator's syntax and accessibility messages, as well as user feedback and human site testing, you'll be well on your way toward having a quality, accessible website that works for everyone.

Please note that although CSS HTML Validator is an essential tool for producing accessible and usable websites, no computer program can find all accessibility and usability issues. Therefore, we strongly recommend that you utilize human testing and feedback to find any problems that computer software cannot find.

Ensuring full accessibility often requires a significant amount of manual work. CSS HTML Validator helps you minimize the amount of manual work by quickly checking your documents and finding certain problems before your website is manually tested.

Download a free trial of CSS HTML Validator Pro for Windows (or htmlval for Mac or Linux) to check your website for accessibility and other problems.