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ReferencesWCAG Criteriaaxe-core Rule Index

axe-core Rule Index

ClearSight runs all axe-core rules that map to WCAG 2.1 Level A and AA. Below is a reference of the most commonly flagged rules.

For the full axe-core rule list, see the axe-core documentation .

Critical rules (Level A)

Rule IDDescriptionWCAG
image-altImages must have alternate text1.1.1 A
button-nameButtons must have discernible text4.1.2 A
labelForm elements must have labels1.3.1 A
link-nameLinks must have discernible text2.4.4 A
document-titleDocuments must have a <title> element2.4.2 A
html-has-lang<html> element must have a lang attribute3.1.1 A
keyboardContent must be accessible by keyboard2.1.1 A
duplicate-idIDs must be unique4.1.1 A

Serious rules (Level AA)

Rule IDDescriptionWCAG
color-contrastText must meet 4.5:1 contrast ratio1.4.3 AA
aria-allowed-attrARIA attributes must be allowed for element’s role4.1.2 A
aria-required-attrRequired ARIA attributes must be provided4.1.2 A
aria-valid-attr-valueARIA attribute values must be valid4.1.2 A
landmark-one-mainPage must have one main landmark1.3.1 A
regionAll page content must be contained in landmarks1.3.1 A

Moderate rules

Rule IDDescriptionWCAG
heading-orderHeading levels must only increase by one1.3.1 A
list<ul> and <ol> must contain only <li> elements1.3.1 A
listitem<li> elements must be inside a list1.3.1 A
table-duplicate-nameTable summary and caption must not have the same value1.3.1 A
td-headers-attrTable cells must have headers with valid IDs1.3.1 A

Custom engine rules (not axe-core)

Rule IDEngineDescriptionWCAG
link-text-qualityLinkTextEngineLink text must be descriptive (not “click here”, “read more”)2.4.4 A
touch-target-sizeTouchTargetEngineInteractive elements must be at least 24×24px2.5.5 AA
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Level AA RulesChangelog