Design Apps and Websites That People with Disabilities Can Use (Accessibility)

## Build Accessibility in from the First Idea, Not as a Final Check Include accessibility in the definition of a successful experience from the first concept through maintenance. Do not postpone it as a compliance pass after interaction and visual decisions are fixed. - Define the essential information, tasks, outcomes, and failure consequences. - Identify accessibility requirements alongside functional, privacy, security, and performance requirements. - Assign owners for design, content, implementation, testing, and remediation. - Include accessibility acceptance criteria in each relevant feature or component. - Prefer inclusive defaults while still allowing useful personalization. - Reuse accessible patterns, but verify that they work in the actual context. - Do not trade away access to a core task for visual novelty or implementation convenience. ## Find the Steps That Block People with Different Abilities Study how a task works without assuming one body, sense, device posture, input method, attention span, or processing speed. Consider permanent, temporary, situational, and combined barriers. - Trace each core journey from discovery through completion, error recovery, and confirmation. - Examine visual, auditory, motor, speech, cognitive, and environmental barriers separately. - Identify steps that depend on sight, color, sound, precision, memory, speed, or complex gestures. - Distinguish user needs from a diagnosis and avoid designing around stereotypes. - Prioritize barriers by affected task importance, severity, frequency, and absence of alternatives. - Include people who use assistive technologies in research when practical. - Record assumptions that still require direct evidence. ## Keep Text Readable When Zoomed and Never Rely on Color Alone Ensure text, icons, status, and structure remain understandable under varied vision, lighting, display, and preference conditions. - Support text and interface scaling without clipping, overlap, hidden controls, or lost information. - Choose readable type size, weight, line length, spacing, and hierarchy for the target environment. - Meet the applicable published contrast standard in every supported appearance and state. - Never use color as the only signal for meaning, status, selection, or error. - Pair color with text, shape, iconography, pattern, or position as appropriate. - Preserve meaning under zoom, high contrast, color adjustment, and reduced transparency settings. - Test real rendered states, including disabled, focused, selected, error, and loading states. ## Tell Assistive Tools What Each Part Is and What It Does Provide programmatic semantics that communicate what each element is, what it contains, its current state, and what action it performs. - Use native semantic elements and controls before creating custom equivalents. - Give every meaningful control a concise, unique, context-appropriate accessible name. - Provide useful descriptions for informative images and hide purely decorative content from navigation. - Maintain a logical reading order, focus order, grouping structure, and heading hierarchy. - Announce important dynamic changes without repeatedly interrupting the user. - Keep labels, states, values, errors, and instructions synchronized with the visible interface. - Verify that custom components expose equivalent semantics, actions, and state changes. ## Add Captions and Transcripts for Sound and Video Do not communicate essential information through audio, vision, or haptics alone. Choose alternatives that preserve the purpose, timing, and meaning of the original signal. - Provide synchronized captions for important spoken content and meaningful sounds. - Provide transcripts when people may need a complete searchable or reviewable record. - Describe important visual events that are not available through dialogue or surrounding content. - Pair audio alerts with visible or tactile feedback where it improves recognition. - Pair haptic or visual alerts with another channel when they carry critical meaning. - Let people control playback, captions, volume, and available alternative tracks. - Check that every alternative remains accurate when the primary content changes. ## Make Buttons Easy to Hit and Everything Usable by Keyboard Allow people to complete core tasks with different physical inputs and levels of dexterity. Operability depends on target size, spacing, sequence, alternatives, and predictable behavior together. - Use target sizes and spacing that meet the applicable platform or web standard. - Keep frequent actions simple and avoid requiring complex, simultaneous, or repeated gestures. - Provide a visible control for any essential action that otherwise relies on a gesture. - Support complete keyboard navigation with visible focus and a logical traversal order. - Preserve established shortcuts unless a replacement is necessary and documented. - Label controls so voice, switch, pointer, and other assistive inputs can identify them. - Avoid interactions that demand sustained force, fine precision, or large repetitive movement. ## Keep Steps Simple and Avoid Short Time Limits Make interactions consistent, learnable, and recoverable. Complexity that is optional for experts must not block a clear path through essential tasks. - Use familiar patterns and stable placement for repeated actions. - Break long workflows into focused steps and show progress, context, and a way back. - Prefer explicit dismissal over short automatic timeouts; allow more time when timing is necessary. - Use plain instructions, specific error messages, and visible next actions. - Let people pause or stop moving, audio, and video content that starts automatically. - Offer difficulty, pacing, or assistance settings when task success depends on speed or precision. - Require clear confirmation and a recovery path before difficult-to-reverse actions. ## Cut Motion and Flashing That Can Harm People Use motion only when it improves understanding. Rapid movement, flashing, depth changes, and uncontrolled camera motion can distract, cause discomfort, or create serious health risk. - Honor reduced-motion and reduced-flashing preferences throughout the experience. - Reduce automatic, repetitive, peripheral, zooming, scaling, and depth-based motion. - Provide a calm alternative to effects that are necessary in the default presentation. - Avoid bright frequent flashes and validate media against an applicable safety threshold. - Keep spatial content within a comfortable field of view and avoid rapid attention shifts. - Minimize forced camera movement and large or repetitive body gestures. - Test motion changes for lost context, hidden state, or broken task feedback. ## Follow the Settings People Choose on Their Device Adapt to user-selected settings instead of treating accessibility as a separate mode with fewer capabilities. Preserve task meaning and completion across supported configurations. - Respond correctly to text size, contrast, appearance, motion, caption, and input preferences. - Keep core functionality available when nonessential interface elements are reduced. - Let users choose comfortable colors, timing, playback, difficulty, or control assistance where relevant. - Do not reset accessibility-related choices without a clear reason and notice. - Avoid making users disclose a disability to obtain an accessible path. - Persist preferences predictably while providing an easy route to review or change them. - Test combinations of settings, because individually correct adaptations can conflict. ## Test Each Main Task with a Keyboard and Assistive Tools Before Release Use multiple forms of evidence. Automated checks can find some defects, but they cannot prove that a real task is understandable or usable with assistive technology. - Run automated checks early and repeatedly for detectable structural and visual issues. - Test every core task with keyboard-only and relevant assistive interaction methods. - Inspect focus, labels, reading order, announcements, scaling, contrast, media alternatives, and motion settings. - Include disabled participants or experienced assistive-technology users in evaluation when possible. - Record the environment, method, result, severity, owner, and retest evidence for each finding. - Block release on unresolved defects that prevent access to a core task or create serious harm. - Do not claim conformance or feature support beyond the scope of verified evidence.