In June of 2019 the W3 organization released version 2.1 of the Web Content Accessibility Guidelines (WCAG 2.1) as a candidate release. This post is an overview of what WCAG is, how to understand the guidelines, and a summary of what changed between versions 2.0 and 2.1.
What is WCAG?
The Web Content Accessibility Guidelines, which is usually abbreviated as WCAG and pronounced “wuh-CAG,” is a set of guidelines built by industry experts to help anyone creating web content understand how to make it accessible to a wide variety of users. From the WCAG 2.1 abstract:
- Following these guidelines will make content more accessible to a wider range of people with disabilities, including accommodations for blindness and low vision, deafness and hearing loss, limited movement, speech disabilities, photosensitivity, and combinations of these, and some accommodation for learning disabilities and cognitive limitations; but will not address every user need for people with these disabilities
The goal of WCAG is to define the baseline of accessible web content, and then establish success criteria so that each guideline can be tested to ensure it is being met.
The POUR Acronym
WCAG is divided into 4 sections that make up the acronym POUR: Perceivable, Operable, Understandable, and Robust. Each of these categories represents a different goal for accessible web content.
Under Perceivable are guidelines relating to the many ways that users can perceive web content. This category includes topics like having multiple ways to access content (such as audio files including transcripts), guidelines about time-based media like videos, and guidelines about color and contrast, among others.
These guidelines help web content makers think through the many ways a user may need to access their content, and be more aware of alternative ways that can be presented to give all users the opportunity for access.
The section on Operable covers the many ways that people interact with web content. This section discusses making all content navigable by a keyboard (which extends to other assistive tech), as well as covering the different demands that content might place on users. People who are accessing your content may be using a wide variety of tech, whether it’s screen readers or switch controls or browsing with their eyes via a screen. Accessible web content is operable for all of these scenarios.
Much of the Operable section covers the ways that content is defined by HTML markup and language, which are critical considerations because they determine how assistive tech navigates web content. The considerations in this section are about the structure of content; the way headings create an outline of a page, how users who are using the keyboard to access content move through the page, and whether interactive targets are large enough for users of varying abilities can access them. If you are creating web content on a website platform that has WYSIWYG design capabilities, these guidelines apply to your content but may be pre-determined by the platform.
The WCAG section on Understandable relates to making web content readable and predictable to users. This includes thinking about the language content is written with, so that the content does not demand specific cognitive or educational levels and is available to as many users as possible. It also includes making sure that when users are filling out forms, the error messages they receive if something is incorrect are helpful and useful no matter how they are interacting with the content, among other topics.
The final WCAG section is Robust, which is about making sure web content is presented in ways that do not demand a single mode of access, such requiring visual abilities to see error messages. Instead, a web page should render important messages with the correct HTML markup so that things like screen readers can find and accurately understand them.
The difference between levels A, AA, and AAA
WCAG guidelines are designed to be principles about how web content should work. Because this is a broad goal, every guideline includes success criteria that are ranked via the A, AA, and AAA labels.
Level A is the baseline level of acceptance that all sites should achieve. If sites cannot achieve these guidelines, WCAG allows for providing a “conforming alternate version” which is an accessible page that meets all Level A criteria, provides the same information using the same language (meaning the information presented by the alternate version is not“simplified” or stripped down) and is easily reachable from the page that does not conform.
Level AA is generally understood to be the desired goal for most sites. Designing and building web content with Level AA criteria will ensure that a wide range of users will be able to access and enjoy your web content. As of 2017, Section 508 was updated to set WCAG 2.0 Level AA as the standard for all federal agencies and content.
Level AAA are the most rigorous standards for accessibility, and are best understood as necessary when designing web content for specific audiences with disabilities. WCAG itself notes that “it is not possible to satisfy all Level AAA Success Criteria for some content” and thus Level AAA should not be the policy for entire sites.
What changed from WCAG 2.0 to WCAG 2.1
In June of 2018 WCAG 2.1 was published as a Recommendation document, which means it’s now the current version of WCAG. WCAG 2.1 introduced 17 new guidelines and associated success criteria. The previous version of WCAG was written when mobile devices were less popular and touch screens were on the rise. This version of WCAG addresses new issues of access that have been raised with the popularity of mobile and touch-based devices.
The new guidelines cover things like not locking content to portrait or landscape modes of devices (as many users may be using a device that’s mounted), making sure that buttons and inputs are properly labeled (including using markup that’s available to assistive devices), and covering the size and spacing of elements on a page. There are also guidelines about motion and touch controls, to ensure that users can navigate web content through a variety of means.
The new guidelines represent the best understanding we have as of 2018 for what accessible web content is. Every year the digital tech landscape continues to evolve, and as it does, our understanding of how to make web content accessible to all users will evolve as well. The WCAG guidelines will continue to change, and the industry will hopefully use them to build a web that works for everyone.