Motor and keyboard-only

Level A, 13 rules

• 2.1.1 Keyboard

  This affects blind users driving a screen reader from the keyboard, speech-input users whose software sends keystrokes on their behalf, people using sip-and-puff systems, on-screen keyboards, scanning software or an alternate keyboard, people with tremors or limited hand dexterity, and low-vision users who find tracking a pointer harder than pressing a key.

• 2.1.2 No Keyboard Trap

  This affects every keyboard-dependent visitor, including screen-reader users, switch-device users, speech-input users whose software sends keystrokes, and sighted people who simply prefer typing to clicking.

• 2.1.4 Character Key Shortcuts

  This affects speech-input users, whose dictation is a stream of the same characters a shortcut listens for, keyboard users with a tremor who brush a key and lose their place in a long page, and people with some cognitive disabilities, who benefit from remapping so the same shortcut does the same thing across every application they use.

• 2.2.1 Timing Adjustable

  This affects screen-reader users hearing a form one field at a time, slow typists, people with cognitive or motor disabilities, deaf users for whom the page text is a second language or who are working through a sign language interpreter, and anyone for whom a form takes longer than it did in the demo.

• 2.4.1 Bypass Blocks

  This affects keyboard and switch users, who would otherwise press Tab dozens of times on every page, screen-reader users jumping by landmark or heading, screen-magnifier users hunting for where the main content starts, and people for whom repeated keystrokes are physically painful.

• 2.4.2 Page Titled

  This affects screen-reader users orienting themselves on arrival, people with visual disabilities telling several open pages apart, people with cognitive disabilities, limited short-term memory or reading disabilities, people with severe mobility impairments who work by audio while moving between pages, and everyone scanning a page of search results.

• 2.4.3 Focus Order

  This affects keyboard and screen-reader users moving through the page in sequence, magnification users at high zoom who can read a field in the wrong context entirely, and people with reading or cognitive disabilities who lose their place when focus lands somewhere unexpected.

• 2.4.4 Link Purpose (In Context)

  This affects screen-reader users navigating by link list, voice-control users who speak a link's visible name to follow it, people with motion impairments who need to know which links to skip, and anyone reading search results where the link text is the whole preview.

• 2.5.1 Pointer Gestures

  This affects people with limited dexterity or tremors, people using a head pointer, eye-gaze system, prosthetic or speech-controlled mouse emulator, people working one-handed, screen-reader users on touchscreens whose own software eats the gesture before the page sees it, and people with cognitive or learning disabilities who can fall back on a plain tap where a custom gesture makes no sense to them.

• 2.5.2 Pointer Cancellation

  This affects people with tremors or imprecise touch who brush a control by accident, people with visual disabilities who cannot confirm what they touched, people with cognitive limitations who need a way to back out of an action, people with motor impairments, and anyone who has ever fat-fingered a Delete they did not mean.

• 2.5.4 Motion Actuation

  This affects people using a device on a fixed mount, including a wheelchair mount, a car mount or a stand, people with motor impairments who cannot produce the movement precisely, people with tremors who trigger it without meaning to, and anyone whose device is not free to move at that moment.

• 3.2.1 On Focus

  Keyboard and screen reader users pass through every control on the way to any control, so a page that acts on focus touches almost everything they try to do. People with motor impairments are hit twice, since a tremor or a switch makes an unintended focus more likely in the first place. Users with cognitive disabilities lose their place when a page moves on its own instead of waiting to be asked.

• 3.3.7 Redundant Entry

  People with motor disabilities, including anybody using switch control or voice input, pay for every keystroke twice. People with memory and cognitive disabilities have to rebuild an answer they already gave, sometimes with no way to check what it was. And anybody deep in a long process is more tired at step five than at step one, which is exactly when the form asks them to do it all again.

Level AA, 10 rules

• 1.3.4 Orientation

  Users with motor disabilities whose device is mounted in a fixed position, on a wheelchair arm or a bed frame, cannot rotate it at all. Anyone using a stand or a dock that holds one orientation is in the same position. Low-vision users who read in landscape to fit more words on a line lose that option too.

• 1.3.5 Identify Input Purpose

  People with cognitive disabilities who cannot work out a field's purpose from the label alone are the group this rule was written for. People with cerebral palsy, stroke, head injury, motor neuron disease or a learning disability who use software that puts pictures on form fields depend on the same declaration. So do people with motor disabilities for whom typing is slow and effortful, people with memory difficulties, and anyone mistyping an address on a phone keyboard.

• 1.4.11 Non-text Contrast

  Low-vision users lose pale form fields altogether, and a field they cannot find is a form they cannot fill. Older users hit the same edge, since contrast sensitivity falls with age. Keyboard users need to see where focus has landed, which is the same measurement applied to a different thing. Anyone on a dim or reflective screen runs your whole interface at lower effective contrast than you designed it for.

• 1.4.13 Content on Hover or Focus

  Screen magnifier users need to pan across the screen to read revealed content, and panning means moving the pointer. Users with tremor or low pointer accuracy trigger content they did not mean to and need a way to clear it. People who run a large mouse cursor find it covering the very thing that just appeared. Users with cognitive disabilities need the reading time a timer takes away.

• 2.4.7 Focus Visible

  This affects every sighted keyboard user, who otherwise guesses where the next Enter press will land, and it affects people with attention limitations, short-term memory limitations or executive processing difficulties, who need to see where focus is rather than remember it.

• 2.4.11 Focus Not Obscured (Minimum)

  This affects sighted keyboard users who lose track of focus behind a sticky bar, low-vision users who orient with a pointer and see less of the page at a time under magnification, and people with attention limitations, short-term memory limitations or executive processing difficulties, who lose their place entirely when focus goes out of sight.

• 2.5.7 Dragging Movements

  This affects people with limited dexterity, tremors or fatigue-related conditions, people using a trackball, head pointer, eye-gaze system or speech-controlled mouse emulator, and anyone using a site one-handed on a moving train.

• 2.5.8 Target Size (Minimum)

  This affects people using a touchscreen phone, people with hand tremors, spasticity or quadriplegia using a mouse, stylus or touch, people in a moving vehicle or on public transport, people who find fine mouse movements difficult, people operating a device one-handed, and people with large fingers or those tapping with part of a finger or a knuckle.

• 3.3.3 Error Suggestion

  People with cognitive and learning disabilities are hit hardest, because knowing something is wrong is not the same as knowing what to do. Blind and low-vision users need the fix described rather than shown, since the field will not look wrong to them. People with motor impairments pay for every extra attempt in effort. Everybody else is stuck in the same loop with less at stake.

• 3.3.4 Error Prevention (Legal, Financial, Data)

  People with motor disabilities make more accidental inputs, through no fault of their own, and a page with no safeguard turns each one into a consequence. People with reading disabilities transpose digits, which is how a quantity of 100 becomes 1000 and a travel date lands in the wrong month. Users with cognitive disabilities are likelier to commit to something before they have finished reading it. And everybody else has been saved by a review screen at least once.

Level AAA, 10 rules

No law names AAA as a blanket duty, but these are where the remaining barriers for people who cannot use a mouse, or cannot use one precisely usually sit.

• 2.1.3 Keyboard (No Exception)

  Keyboard users, switch users and voice control users all reach a page through a keyboard interface, which is why this goes further than people typing on a physical keyboard.

• 2.2.3 No Timing

  W3C names blind readers first, then people with low vision, then people with cognitive limitations and people with motor impairments, and adds deaf readers for whom written text is a second language.

• 2.4.9 Link Purpose (Link Only)

  People with motion impairments, people with cognitive limitations, and screen reader users pulling up a list of a page's links are the three groups W3C names.

• 2.4.10 Section Headings

  Blind readers, keyboard users, people with learning disabilities and anybody skimming rather than reading straight through all use the same structure.

• 2.4.12 Focus Not Obscured (Enhanced)

  Sighted keyboard users are the main group, and that includes people using speech input, sip-and-puff switches, on-screen keyboards and scanning software. People with low vision using magnification, and people with attention or short-term memory limitations, are the other two W3C names.

• 2.4.13 Focus Appearance

  Anybody who works the page by keyboard, and W3C's own summary names older readers first among the people who cannot see a small change in appearance.

• 2.5.5 Target Size (Enhanced)

  People with tremor or reduced dexterity, people with large fingers or tapping with a knuckle, anybody using a phone one-handed, and anybody tapping on a moving bus. W3C names low vision too, since a bigger target is easier to see as well as to hit.

• 2.5.6 Concurrent Input Mechanisms

  Anybody who alternates input methods, which covers most touchscreen laptop users and most assistive technology users. W3C's own examples name a reader with a mobility impairment pairing a keyboard and mouse to a phone, somebody with hand tremors or limited dexterity reaching for the keyboard when a target is too small for the touchscreen, and a speech-input user switching to the mouse when a colleague starts talking.

• 3.2.5 Change on Request

  Screen reader users, people with low vision, people with motor impairments and people with cognitive limitations are the four groups W3C names.

• 3.3.6 Error Prevention (All)

  People with cognitive disabilities, people with motor disabilities who are more likely to mistype or mis-click, and honestly anybody who has ever pressed submit by mistake. W3C names transposing numbers and hitting keys by accident specifically.

Other groups

• Blind and screen reader users40 rules
• Low vision35 rules
• Deaf and hard of hearing9 rules
• Voice control13 rules
• Cognitive and learning50 rules
• Seizures and vestibular disorders4 rules