Learn
Which rules matter for which people
WCAG is filed by principle, by level and by guideline, and not one of those tells you who a rule is for. This page turns the standard round. Pick the group you have in mind and you get the criteria whose own text names those people, so a team building for deaf visitors or for switch users has somewhere to start rather than 86 rules in numerical order.
How these groups were made, and what they leave out
Every criterion page carries a note saying who feels it when that rule fails, and these groups are read from those notes rather than assigned by hand. Two things follow. A criterion turns up under a group only when its own note names those people, which is a narrower promise than every rule that could ever matter to them. And because most notes name several groups at once, the 7 counts below come to 184 mentions across 86 of the 86 criteria in the standard.
W3C makes the harder point about sorting people this way. It asks you to think in terms of the broad diversity of functional needs rather than to categorize people by medical classification, and it says its own examples are not a complete list of disabilities or barriers. Plenty of people have several disabilities at once, or one that changes through the day, or one they would never call a disability. So treat each list as where to start rather than as the edge of your duty.
Blind and screen reader users
40 rules · 31 at A or AA
A screen reader turns the page into speech, or into braille under somebody's fingers, and it can only hand on what the code actually said. Anything left out of the markup does not exist here. Which is why most of this list is about names, structure and reading order, and almost none of it is about how the page looks.
Low vision
35 rules · 23 at A or AA
Far more people have low vision than are blind, roughly six of every seven with a visual impairment, and many people who are legally blind still read a screen when it is set up the way they need it. So this is not one reader. It is somebody magnifying, somebody recolouring, somebody zoomed to four times the original size, and somebody whose ideal settings are the opposite of the person's beside them.
Deaf and hard of hearing
9 rules · 5 at A or AA
Anything the site says out loud has to exist somewhere else as well. Captions are the obvious answer and they are not the only one, because a transcript is not a caption, a caption is not sign language, and what you owe depends on what the media actually contains. Captions on prerecorded video sit at Level A, which is the floor every conformance target is built on, so there is no version of this you get to defer.
Motor and keyboard-only
33 rules · 23 at A or AA
Keyboards, switches, head pointers and eye trackers all answer the same problem in different ways. Pointing accurately is slow, painful or impossible, so the interface has to be reachable without it. The group is wider than the equipment makes it sound, though. Arthritis, tremor, pain, fatigue and a wrist somebody broke last month all land in the same place, and most of the people here are using nothing you would recognise as assistive technology.
Voice control
13 rules · 10 at A or AA
Voice control matches what somebody says out loud against the labels they can see. Say "click Add to basket" and the software goes looking for a control whose name contains those words. The visible label is the command, which makes this the one input method where the words on a button are functional rather than decorative. It ships with macOS, iOS, Windows and Android, so most people using it are using software that came with the device.
Cognitive and learning
50 rules · 30 at A or AA
This covers memory, attention, processing speed, reading, comprehension and executive function, which takes in dyslexia, ADHD, autism, brain injury, early dementia, anxiety and depression, along with anybody trying to finish something while distracted, exhausted or under time pressure. Overall intelligence is usually untouched, and that is the most misunderstood thing about the whole category. More of these rules name this group than name any other, and most of the work behind them has no test you can automate.
Seizures and vestibular disorders
4 rules · 2 at A or AA
This is the smallest set on the site and the only one where getting it wrong makes somebody physically ill. Flashing can trigger a seizure. Large moving imagery can bring on nausea, migraine, and dizziness bad enough that the guidance behind these rules talks about needing bed rest afterwards. None of it is a matter of taste, and none of it is answered by telling people to look away.
Four other ways into the same 86 rules
- Level AA is the bar the laws actually name.
- All 55 Level A and AA rules follow the structure WCAG itself uses.
- Find the rule from what broke takes a description instead of a number.
- The printable checklists turn the rules into a sequence you can run.