3 Understandable
Information and the operation of the user interface must be understandable.
3.1 Readable
Make text content readable and understandable.
3.1.1 Language of Page
Conformance level: A
Specify the default language of the web page.
3.1.2 Language of Parts
Conformance level: AA
Identify the language of each passage or phrase.
3.1.3 Unusual Words
Conformance level: AAA
Provide definitions for unusual words or jargon.
3.1.4 Abbreviations
Conformance level: AAA
Provide expanded forms or definitions for abbreviations.
3.1.5 Reading Level
Conformance level: AAA
Ensure content is readable and understandable, ideally at a lower secondary education level.
3.1.6 Pronunciation
Conformance level: AAA
Provide a way to determine the pronunciation of words where meaning is ambiguous.
3.2 Predictable
Make Web pages appear and operate in predictable ways.
3.2.1 On Focus
Conformance level: A
Ensure elements do not initiate a change of context when they receive focus.
3.2.2 On Input
Conformance level: A
Ensure changes of context are initiated only on user request.
3.2.3 Consistent Navigation
Conformance level: AA
Use consistent navigation mechanisms across pages.
3.2.4 Consistent Identification
Conformance level: AA
Ensure components that have the same functionality are identified consistently.
3.2.5 Change on Request
Conformance level: AAA
Ensure changes of context are initiated only upon user request.
3.2.6 Consistent Help
Conformance level: A
Put help in the same place when it is on multiple pages.
3.3 Input Assistance
Help users avoid and correct mistakes.
3.3.1 Error Identification
Conformance level: A
Identify input errors and provide text descriptions.
3.3.2 Labels or Instructions
Conformance level: A
Provide labels or instructions when content requires user input.
3.3.3 Error Suggestion
Conformance level: AA
Provide suggestions for correcting input errors.
3.3.4 Error Prevention (Legal, Financial, Data)
Conformance level: AA
Reduce the risk of input errors for critical data.
3.3.5 Help
Conformance level: AAA
Provide context-sensitive help.
3.3.6 Error Prevention (All)
Conformance level: AAA
Ensure submissions can be reviewed, corrected, and confirmed.
3.3.7 Redundant Entry
Conformance level: A
Don't ask for the same information twice in the same session.
3.3.8 Accessible Authentication (Minimum)
Conformance level: AA
Don’t make people solve, recall, or transcribe something to log in.
3.3.9 Accessible Authentication (Enhanced)
Conformance level: AAA
Don’t make people recognize objects or user-supplied images and media to login.