This resource is designed for anyone eager to master digital accessibility. Explore WCAG success criteria through clear, easy-to-understand descriptions. We owe a special "hat tip" to Johannes Lehner’s WCAG Card Deck, which served as the inspiration for this project.
We plan to expand this library over time, so please check back regularly for updates.
87 success criteria found
Level Level A, WCAG principle: Perceivable
Assigned to the following themes: CODE AND LABELS SENSORY WORDING
All images and other non-text content (like icons, charts, audio, CAPTCHAs, or controls) must have a descriptive text alternative that conveys their meaning. Purely decorative content can be hidden from assistive technologies (e.g. using an empty alt attribute).
Level Level A, WCAG principle: Perceivable
Assigned to the following themes: SENSORY WORDING
Prerecorded audio-only content must have a text transcript. Prerecorded video-only content must have a text or audio description.
Level Level A, WCAG principle: Perceivable
Assigned to the following themes: SENSORY WORDING
Prerecorded videos with audio must have synchronised captions that include:
Level Level A, WCAG principle: Perceivable
Assigned to the following themes: SENSORY WORDING
Important visual content in prerecorded videos must be described using:
Level Level AA, WCAG principle: Perceivable
Assigned to the following themes: SENSORY WORDING
Live video with audio must include real-time captions that cover:
Level Level AA, WCAG principle: Perceivable
Assigned to the following themes: SENSORY WORDING
Important visual content in prerecorded videos with audio must be described using:
Level Level AAA, WCAG principle: Perceivable
Assigned to the following themes: SENSORY WORDING
All prerecorded videos with audio must include a sign language interpretation.
Level Level AAA, WCAG principle: Perceivable
Assigned to the following themes: SENSORY WORDING
Prerecorded videos must include extended audio descriptions if important visual content like:
can't be described during normal playback.
Level Level AAA, WCAG principle: Perceivable
Assigned to the following themes: SENSORY WORDING
Prerecorded videos must have a full text alternative that includes:
even if captions and audio descriptions are already available.
Level Level AAA, WCAG principle: Perceivable
Assigned to the following themes: SENSORY WORDING
Live audio-only content must include a real-time text alternative, such as:
Level Level A, WCAG principle: Perceivable
Assigned to the following themes: CODE AND LABELS WORDING
Visual information and relationships (like labels, headings, or groupings) must also be conveyed in the code using:
so that assistive technologies can understand the structure.
Level Level A, WCAG principle: Perceivable
Assigned to the following themes: CODE AND LABELS WORDING
Content must follow a logical and meaningful order in the code so it can be understood correctly by assistive technologies even if the visual layout differs.
Level Level A, WCAG principle: Perceivable
Assigned to the following themes: FORMS SENSORY WORDING
Instructions and descriptions must not rely on sensory features alone, like color, shape, size, visual location, or sound.
Always provide additional text to clarify meaning.
Level Level AA, WCAG principle: Perceivable
Assigned to the following themes: GESTURES
Content must remain readable and usable in both portrait and landscape orientation, unless a specific one is essential (e.g. in a piano app that requires landscape to show the full keyboard).
Level Level AA, WCAG principle: Perceivable
Assigned to the following themes: FORMS
The purpose of common form fields (like name, email, or address) must be defined in the code so that browsers and assistive technologies can offer input support, such as autocomplete.
Level Level AAA, WCAG principle: Perceivable
Assigned to the following themes: FORMS
The purpose of regions and common elements must be defined in the code using semantic HTML or ARIA attributes, so that:
Level Level A, WCAG principle: Perceivable
Assigned to the following themes: SENSORY
Colour must not be the only way to convey information.
Always provide an additional visual cue, like icon, text label, underline, shape, or pattern (e.g. striped, solid).
Level Level AA, WCAG principle: Perceivable
Assigned to the following themes: GESTURES ZOOM AND LEGIBILITY
Content remains functional and easy to read when:
without needing to scroll in two directions (except for tables, maps, and similar content).
Level Level AA, WCAG principle: Perceivable
Assigned to the following themes: SENSORY
Interactive controls (e.g. buttons, form fields, focus indicators) and graphics that convey meaning (e.g. icons, charts, graph lines) must have a contrast ratio of at least 3:1 against adjacent colours.
Level Level AA, WCAG principle: Perceivable
Assigned to the following themes: ZOOM AND LEGIBILITY
Text remains readable and usable when spacing is changed using custom styles to at least:
without content being hidden, cut off, or broken.
Level Level AA, WCAG principle: Perceivable
Assigned to the following themes: GESTURES KEYBOARD ZOOM AND LEGIBILITY
When additional content appears on hover or keyboard focus (including long press on touch), it must:
Level Level A, WCAG principle: Perceivable
Assigned to the following themes: SENSORY
If audio plays automatically for more than 3 seconds, it must be possible to:
without using system-wide controls.
Level Level AA, WCAG principle: Perceivable
Assigned to the following themes: SENSORY ZOOM AND LEGIBILITY
Text contrast against its background must be at least:
Level Level AA, WCAG principle: Perceivable
Assigned to the following themes: ZOOM AND LEGIBILITY
Text remains readable and usable when zoomed to 200%.
Level Level AA, WCAG principle: Perceivable
Assigned to the following themes: SENSORY ZOOM AND LEGIBILITY
Text must be actual text, not images of text, unless a specific visual presentation is absolutely necessary (e.g. logo).
Level Level AAA, WCAG principle: Perceivable
Assigned to the following themes: SENSORY ZOOM AND LEGIBILITY
Text contrast against its background must be at least:
Level Level AAA, WCAG principle: Perceivable
Assigned to the following themes: SENSORY
For prerecorded audio with speech, any background sound must be:
Level Level AAA, WCAG principle: Perceivable
Assigned to the following themes: SENSORY ZOOM AND LEGIBILITY
Blocks of text (like paragraphs) must:
allow users to adjust spacing and colors using custom styles.
Level Level AAA, WCAG principle: Perceivable
Assigned to the following themes: SENSORY ZOOM AND LEGIBILITY
Text must be actual text, not images of text (no exception, not even for design or aesthetic reasons).
Level Level A, WCAG principle: Operable
Assigned to the following themes: KEYBOARD
All functionality must be operable using a keyboard alone, unless the task requires freehand input (e.g. drawing).
Level Level A, WCAG principle: Operable
Assigned to the following themes: KEYBOARD
It must always be possible to move focus into and out of any component using a keyboard alone (e.g. [tab], [shift]+[tab], [enter], [esc]), without getting stuck.
Level Level AAA, WCAG principle: Operable
Assigned to the following themes: KEYBOARD
All functionality must be operable using a keyboard alone (no exception, not even for tasks involving gestures like drag-and-drop or pointer-based interaction).
Level Level A, WCAG principle: Operable
Assigned to the following themes: KEYBOARD
Keyboard shortcuts should use modifier keys like [ctrl], [cmd], or [alt/option]. If single-key shortcuts are used (e.g. 'S' for save), it must be possible to:
Level Level A, WCAG principle: Operable
Assigned to the following themes: FORMS SENSORY
Time limits must be avoided unless essential for the task (e.g. exams, auctions). If time limits are used, it must be possible to:
Level Level A, WCAG principle: Operable
Assigned to the following themes: SENSORY
If content moves, scrolls, blinks, or updates automatically for more than 5 seconds, it must be possible to:
Level Level AAA, WCAG principle: Operable
Assigned to the following themes: FORMS SENSORY
Content must not include time limits for reading or interaction, unless it's part of a live event or time-based activity (e.g. auctions, broadcasts).
Level Level AAA, WCAG principle: Operable
Assigned to the following themes: SENSORY
Interruptions (like pop-ups, alerts, or notifications) must be able to be:
except in emergencies (e.g. critical system warnings).
Level Level AAA, WCAG principle: Operable
Assigned to the following themes: FORMS
If a logged-in session expires mid-way through a task, any data entered after expiry is kept, so that they don’t have to re-enter it when they log in again.
Level Level AAA, WCAG principle: Operable
Assigned to the following themes: FORMS
A warning is shown if a logged-in session is about to expire.
Level Level A, WCAG principle: Operable
Assigned to the following themes: SENSORY
Content must not flash, blink, or flicker more than three times per second, unless it stays within safety limits designed to avoid visual overload and reduce the risk of seizures.
Level Level AAA, WCAG principle: Operable
Assigned to the following themes: SENSORY
Content must not flash, blink, or flicker more than three times per second (no exception, not even if it meets safety thresholds).
Level Level AAA, WCAG principle: Operable
Assigned to the following themes: SENSORY
Animations triggered by interaction (e.g. on click, hover, tap) must be possible to:
Level Level A, WCAG principle: Operable
Assigned to the following themes: KEYBOARD
It must be possible to skip repeated blocks of content (e.g. navigation, header) and jump directly to the main part of the page.
Level Level AAA, WCAG principle: Operable
Assigned to the following themes: CODE AND LABELS
Related content must be organized into clear sections using headings.
Level Level AA, WCAG principle: Operable
Assigned to the following themes: KEYBOARD
When an element receives focus, it must be at least partially visible.
Level Level AAA, WCAG principle: Operable
Assigned to the following themes: KEYBOARD
When an element receives focus, it must be fully visible and not covered by other content.
Level , WCAG principle: Operable
Assigned to the following themes: KEYBOARD SENSORY
The visible focus indicator must:
Level Level A, WCAG principle: Operable
Assigned to the following themes: CODE AND LABELS WHOLE SITE WORDING
Each page must have a unique and descriptive <title> that reflects its topic or purpose.
Level Level A, WCAG principle: Operable
Assigned to the following themes: KEYBOARD
Focus must follow a logical and meaningful order that preserves relationships and matches how the page is naturally read, regardless of layout or language direction.
Level Level A, WCAG principle: Operable
Assigned to the following themes: CODE AND LABELS WORDING
The purpose of each link must be clear from:
Level Level AA, WCAG principle: Operable
Assigned to the following themes: WHOLE SITE
At least two different ways must be available to find pages or content (e.g. navigation menus, on-page links, site search, or a sitemap).
Level Level AA, WCAG principle: Operable
Assigned to the following themes: CODE AND LABELS WORDING
Headings must describe what follows.
Labels and buttons must clearly communicate what information is needed or what action will happen.
Level Level AA, WCAG principle: Operable
Assigned to the following themes: KEYBOARD SENSORY
A visible indicator must show which element is currently focused when navigating with a keyboard.
Level Level AAA, WCAG principle: Operable
Assigned to the following themes: WHOLE SITE
It must be clear where you are within a set of pages (e.g. using breadcrumbs, highlighted menu items, or headings).
Level Level AAA, WCAG principle: Operable
Assigned to the following themes: CODE AND LABELS WORDING
The purpose of each link must be clear:
Level Level A, WCAG principle: Operable
Assigned to the following themes: GESTURES
Actions that rely on gestures (like swiping or pinching) must also be possible using a single tap, click, or button.
Level Level A, WCAG principle: Operable
Assigned to the following themes: GESTURES
Actions must not trigger on press or touch down. They must only trigger on release (like mouse-up or finger lift).
Level Level A, WCAG principle: Operable
Assigned to the following themes: CODE AND LABELS FORMS
The visible text of a button, link, or form field must also be part of its accessible (programmatic) name.
Level Level A, WCAG principle: Operable
Assigned to the following themes: GESTURES
If an action can be triggered by motion (like shaking or tilting the device), it must also:
Level Level AAA, WCAG principle: Operable
Assigned to the following themes: GESTURES
Targets for touch or mouse must be at least 44×44px, unless they are:
Level Level AAA, WCAG principle: Operable
Assigned to the following themes: GESTURES KEYBOARD
It must be possible to switch between input types (mouse, keyboard, touch, voice) without losing access to any functionality.
Level Level AA, WCAG principle: Operable
Assigned to the following themes: GESTURES
Actions that require dragging (like reordering) must also be possible using buttons or another method that does not require dragging.
Level Level AA, WCAG principle: Operable
Assigned to the following themes: GESTURES
Targets must be at least 24×24px, unless they are:
Level Level A, WCAG principle: Understandable
Assigned to the following themes: CODE AND LABELS WORDING
Each page must have a <html lang=""> attribute that matches the main language of the page.
Level Level AA, WCAG principle: Understandable
Assigned to the following themes: CODE AND LABELS WORDING
Any parts of the content in a different language must be marked with the correct lang attribute.
Expressions borrowed from another language (like "déjà vu" in English) do not need this, unless pronunciation or understanding would be affected.
Level Level AAA, WCAG principle: Understandable
Assigned to the following themes: WORDING
Unusual terms, jargon, or figurative language should be:
Level Level AAA, WCAG principle: Understandable
Assigned to the following themes: WORDING
Abbreviations and acronyms should be:
Level Level AAA, WCAG principle: Understandable
Assigned to the following themes: WORDING
If content requires reading skills above lower secondary education (around 9th grade), provide:
to help with understanding.
Level Level AAA, WCAG principle: Understandable
Assigned to the following themes: WORDING
If a word can be pronounced in different ways with different meanings, the intended meaning must be clarified to avoid confusion or ambiguity.
Level Level A, WCAG principle: Understandable
Assigned to the following themes: KEYBOARD
No unexpected changes must happen when an element receives focus (like open a popup, move focus, submit a form).
Level Level A, WCAG principle: Understandable
Assigned to the following themes: CODE AND LABELS FORMS KEYBOARD
No unexpected changes must happen when a field value changes (like auto-submit, reload, open new page).
Level Level AA, WCAG principle: Understandable
Assigned to the following themes: WHOLE SITE
Navigation elements (like menus, links, search) must appear in the same place and order across pages.
Level Level AA, WCAG principle: Understandable
Assigned to the following themes: WHOLE SITE
Elements with the same function must look, behave, and be labeled the same way across pages.
Level Level AAA, WCAG principle: Understandable
Assigned to the following themes: FORMS KEYBOARD
Major changes (like open dialog, navigate, submit) must only happen when explicitly requested.
Level Level A, WCAG principle: Understandable
Assigned to the following themes: WHOLE SITE
Help options (like contact link, support widget) must appear in the same place across pages.
Level Level A, WCAG principle: Understandable
Assigned to the following themes: FORMS WORDING
Errors and validation must be clearly identified and described in text, not just visually (like color or highlighting).
Level Level A, WCAG principle: Understandable
Assigned to the following themes: CODE AND LABELS FORMS
Form fields must have clear labels or instructions to avoid confusion and help complete the input correctly.
Level Level AA, WCAG principle: Understandable
Assigned to the following themes: FORMS WORDING
Errors and validation messages must show text that:
Level Level AA, WCAG principle: Understandable
Assigned to the following themes: FORMS WORDING
Important forms like a legal agreement or submitting financial information offer the opportunity to check the information entered before sending.
Level Level AAA, WCAG principle: Understandable
Assigned to the following themes: FORMS WORDING
Provide additional help (like text instructions, help links, or tooltips) when label alone might be ambiguous or confusing.
Level Level AAA, WCAG principle: Understandable
Assigned to the following themes: FORMS WORDING
Before submitting, all forms must allow:
Level Level A, WCAG principle: Understandable
Assigned to the following themes: FORMS
Don't ask for the same information twice in the same process.
Provide pre-filled fields or selection options if the information was already given.
Level Level AA, WCAG principle: Understandable
Assigned to the following themes: FORMS
Authentication must not rely on memory alone.
Allow copy-paste, password managers, or other options (like email verification).
Level Level AAA, WCAG principle: Understandable
Assigned to the following themes: FORMS
Authentication must not rely on memory or recognition (like solving puzzles, remembering images, or using CAPTCHAs).
Level Level A, WCAG principle: Robust
Assigned to the following themes: CODE AND LABELS
This used to require HTML with proper structure and no critical markup errors (like missing tags or duplicate IDs).
The requirement is removed but still helps with compatibility.
Level Level A, WCAG principle: Robust
Assigned to the following themes: CODE AND LABELS FORMS KEYBOARD
Interactive elements must have:
so that assistive technologies can interpret and interact with them correctly.
Level Level AA, WCAG principle: Robust
Assigned to the following themes: CODE AND LABELS FORMS
Status updates (like "form sent" or "5 items in cart") must: