People learning at a desk.

The reason we make our websites accessible is so that people with disabilities can access the content and engage with the functionality of our website.


There are several disabilities that we take into account when making our websites accessible.

  • Blindness or visual impairments
  • Deafness or hard-of-hearing
  • Motor skills impairments
  • Cognitive disabilities
  • Learning disabilities

Note that people may have one or more disabilities and there are different ranges of disability.

When we improve accessibility, we ensure that our websites are accessible to people with different disabilities and people using assistive technology such as screen readers and voice dictation software.


The Web Content Accessibility Guidelines (WCAG) are technical standards for web accessibility that provide direction on how to make a website (or other web asset) accessible to people with disabilities.

WCAG is authored by the Web Accessibility Initiative (WAI)
of the World Wide Web Consortium (W3C), the main international standards organization for the World Wide Web.

Although WCAG is not the law, it is frequently referenced as a basis for determining whether or not a website is accessible. Some laws, including Section 508 of the Rehabilitation Act of 1973 and the Accessibility for Ontarians with Disabilities Act (AODA), have incorporated WCAG 2.0 AA into the law.


There are four versions of WCAG (1.0, 2.0, 2.1, 2.2) and three conformance
levels (A, AA, AAA). Because AAA is extremely strict, level AA conformance is the defacto conformance level referenced.

Version 2.0 is best viewed as the classic version. It was published in 2008 and
provides a strong baseline for accessibility.

Version 2.1 was published in 2018 and includes key mobile

Version 2.2 was published in 2023 and is the current version.

Success Criteria

Each version and conformance level of WCAG is comprised of success criteria or requirements for conformance.

Think of success criteria as things to do for accessibility.

WCAG 2.0 AA is comprised of 38 success criteria.

WCAG 2.1 AA has 50.

WCAG 2.2 AA has 55.

Other than one exception with 2.2, no previous success criteria change. In other words, each successive version of WCAG builds off the previous.

For example, WCAG 2.1 AA is comprised of 50 success criteria. The only difference between 2.1 and 2.0 is that 2.1 adds 12 additional success criteria.

As such, if your website is conformant with one version and conformance level, then it would also be conformant with a previous version and conformance level.

Stated another way, WCAG 2.1 AA encompasses WCAG 2.0 AA.


While there are literally dozens of success criteria to work on, here is a quick checklist of key considerations to help illustrate how you would account for your website’s accessibility:

  • Ensure meaningful images have concise and descriptive alt text
  • Ensure the website is fully navigable by a keyboard only (no mouse)
  • Provide name, state, role and/or value programmatically for all interactive elements
  • Provide descriptive error messages on form field errors that can be detected through automation
  • Provide at least one way to bypass repeated blocks of content
  • Ensure all videos with sound have accurate closed captions
  • Ensure a color contrast ratio of 4.5:1 is met for all normal text
  • Use semantics so that informational and relationship meaning is preserved

There are many more ways we can improve the accessibility of our website, but this list will get you in the right frame of mind.

While these considerations may seem arbitrary, they are all derived from WCAG. Once you understand these technical standards, you will have a much better awareness of considerations to make when editing code or uploading new content.

While some accessibility considerations are simple and non-technical, others will require someone with experience in web development to implement.