Website accessibility is vital for website designers, developers, and content authors to understand.
Websites rely heavily on users' ability to see, hear, and navigate with their hands. People who can't do that because of sensory, intellectual, learning, and physical disabilities are left without full access to your site. That can be considered discriminatory — and you could be losing out on customers.
To help those who build websites achieve accessibility, the World Wide Web Consortium (W3C) developed a series of standards called the Web Content Accessibility Guidelines (WCAG) to eliminate many of the barriers people with disabilities face when navigating a site.
What are the Web Content Accessibility Guidelines?
WCAG is a shared, international standard developed by many stakeholders, including "industry, disability organizations, government, and accessibility research organizations," according to W3C.
The standard is organized around four principles — perceivable, operable, understandable, and robust, sometimes referred to as POUR. Specific success criteria fall under these umbrellas, such as using descriptive ALT text for images or adding closed captions to videos.
WCAG is a living standard that's updated over time. The most recent iteration is WCAG 2.1, published in June 2018, which includes the previous version (WCAG 2.0) and adds a few more success criteria.
It's also important to know that WCAG is a guide, not a law — it represents best practices, not legal requirements. However, it's widely referenced in legal requirements by international, federal, and state governments. While website accessibility isn't specifically mentioned in the Americans with Disabilities Act, court decisions increasingly look at WCAG compliance in their judgments.
We're not lawyers here, so none of this constitutes legal advice — but making an effort to conform to the standards may put you in a good position to react to future legal requirements, and could offer some protection against legal action.
How can my site conform with the WCAG standard?
Because there are so many success criteria under WCAG (you can reference them all here), the standard's developers recognize that full compliance may not be possible for every site owner, so they categorize sites into three levels of conformance:
- A — the lowest, or bare-minimum conformance level
- AA — the mid-range conformance level
- AAA — the highest level of conformance
The W3C considers AA conformance the typical goal for most website owners, and it's the standard included in most legal requirements. Level A is considered unacceptable, while level AAA is ideal but may not be achievable for all content.
How should I get started with website accessibility?
First, familiarize yourself with the WCAG success criteria — just enough to get an idea of what's expected under the four main principles.
To make your site perceivable, users must be able to perceive it using one of their available senses, so information can't rely on a single sense. Success criteria include:
- Captions for audio content
- Descriptions for video content
- Color contrast ratio of at least 4.5:1
- Resizable text
Operable sites can be navigated effectively by all users — that means navigation options for keyboards and voice control, not just a mouse. Success criteria include:
- Automatically moving content can be paused, stopped, or hidden
- Users have enough time to read content
- Pages have proper titles
- Users can determine the purpose of each hyperlink from the link text alone
Users should be able to understand information as well as navigation to achieve an understandable site. Success criteria include:
- The default language is specified, and unusual words, abbreviations, and pronunciations are defined
- Labels are provided when content requires user input
- Navigation mechanisms repeated on multiple pages appear in the same order on each page
A robust site should have maximum compatibility with current assistive technologies. Success criteria include:
- Elements have complete start and end tags, are nested according to specification, don't duplicate attributes, and have unique IDs
- The name and role of all user-interface components can be programmatically determined
Next, you'll want to determine your site's accessibility by evaluating its elements — but you don't have to do this alone; there are checklists and tools to help.
How do I know if my site is accessible?
While the WCAG standards are a great step forward, the reality is that they're complicated — sometimes even confusing — and don't come with a lot of instruction on how to meet the success criteria. The bottom line: we don't recommend navigating the complexities of WCAG solo.
For beginners, there are plenty of tools to help you measure success, ranging from barely-useful basic checks to robust, comprehensive evaluations. You can quickly evaluate any site with the free WAVE tool, which produces a list of accessibility errors for any URL. Automated tools like it are good places to start, but they have limits in checking against every success criterion.
As your site grows in complexity and traffic, we recommend more powerful tools, like accessiBe's accessWidget for WordPress. And working with developers like us — especially if you're launching or redesigning — gives you the best chance of success, because we can build many of the success-criteria elements from the ground up.
Above all, consider accessibility as you build and update your site, so you're delivering the best experience to the most people.