--- title: Accessibility description: Every Accessibility rule svelte-vitals runs. --- {/* rules-index:start */} ARIA validity, landmark structure, accessible names, and semantic markup: what makes a site usable for everyone. | Rule | Severity | Summary | | ----------------------------------------------------------------------- | ---------- | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | | [`a11y/accessible-name`](/rules/a11y/accessible-name) | 🟡 warning | A button, link, image button, or iframe needs a way to compute its accessible name. | | [`a11y/aria-hidden-focus`](/rules/a11y/aria-hidden-focus) | 🟡 warning | A keyboard-focusable element must not be hidden from assistive technology with aria-hidden="true". | | [`a11y/disallowed-aria-props`](/rules/a11y/disallowed-aria-props) | 🟡 warning | An aria-\* attribute the element's role does not support is ignored; one the role prohibits, such as a name on a bare div, is a name that is not exposed. | | [`a11y/disallowed-element`](/rules/a11y/disallowed-element) | 🟡 warning | Reports every occurrence of the elements a project declares it does not want, and nothing until something is declared. | | [`a11y/duplicate-landmark`](/rules/a11y/duplicate-landmark) | 🟡 warning | A route should have at most one main, banner, and contentinfo landmark. | | [`a11y/id-duplication`](/rules/a11y/id-duplication) | 🟡 warning | Every id in a route should be unique. | | [`a11y/interactive-nesting`](/rules/a11y/interactive-nesting) | 🟡 warning | An interactive element should not sit inside another interactive element. | | [`a11y/invalid-aria-value`](/rules/a11y/invalid-aria-value) | 🟡 warning | An aria-\* attribute's value should match the type the WAI-ARIA spec defines for it. | | [`a11y/invalid-role`](/rules/a11y/invalid-role) | 🟡 warning | A role attribute should name a concrete WAI-ARIA role, not a typo or an abstract role. | | [`a11y/label-has-control`](/rules/a11y/label-has-control) | 🟡 warning | A label needs a for attribute or a wrapped control to be associated with the field it names. | | [`a11y/no-accesskey`](/rules/a11y/no-accesskey) | 🟡 warning | The accesskey attribute assigns a page-level shortcut key whose actual combination varies by browser and OS, is undiscoverable, and conflicts with assistive-technology bindings. | | [`a11y/no-autofocus`](/rules/a11y/no-autofocus) | 🟡 warning | autofocus moves focus on page load without the user asking, so screen reader users lose the page context they were building and keyboard users are dropped mid-page. | | [`a11y/no-missing-id-ref`](/rules/a11y/no-missing-id-ref) | 🟡 warning | An id reference should point to an id that exists somewhere in the composed route. | | [`a11y/permitted-contents`](/rules/a11y/permitted-contents) | 🟡 warning | Every element must be permitted content of its parent, per the HTML content models. | | [`a11y/placeholder-label-option`](/rules/a11y/placeholder-label-option) | 🟡 warning | A required, single-selection select needs an empty first option so users can't submit it unchanged. | | [`a11y/positive-tabindex`](/rules/a11y/positive-tabindex) | 🟡 warning | A tabindex above 0 puts the element ahead of every naturally-ordered element on the page, so a single tabindex="1" reorders keyboard navigation globally. | | [`a11y/required-aria-props`](/rules/a11y/required-aria-props) | 🟡 warning | A role that requires state or property attributes needs them present, unless native host semantics already supply them. | | [`a11y/required-element`](/rules/a11y/required-element) | 🟡 warning | Every route must contain the elements a project declares, judged on the composed route, so a layout's <main> counts. | | [`a11y/top-level-landmark`](/rules/a11y/top-level-landmark) | 🟡 warning | A banner, main, complementary, or contentinfo landmark should not be nested inside another landmark. | | [`a11y/unknown-aria-attribute`](/rules/a11y/unknown-aria-attribute) | 🟡 warning | An aria-\* attribute should name a real WAI-ARIA attribute, not a typo. | | [`a11y/abbr-title`](/rules/a11y/abbr-title) | 🔵 info | An <abbr> without a title gives readers no expansion. Visual users get no tooltip and assistive technology has nothing to expand. | | [`a11y/deprecated-aria`](/rules/a11y/deprecated-aria) | 🔵 info | A role or aria-\* attribute ARIA 1.3 has deprecated, globally or on the role it sits on, still works today and is no longer defined there. | | [`a11y/deprecated-attr`](/rules/a11y/deprecated-attr) | 🔵 info | An attribute the HTML spec data marks deprecated on this element has its behavior defined by legacy compatibility, not by the standard. | | [`a11y/deprecated-element`](/rules/a11y/deprecated-element) | 🔵 info | An element in the HTML standard's obsolete-features list is non-conforming and has a conforming replacement. | | [`a11y/doctype`](/rules/a11y/doctype) | 🔵 info | src/app.html should open with <!doctype html>. | | [`a11y/no-duplicate-dt`](/rules/a11y/no-duplicate-dt) | 🔵 info | Within a single dl element there should not be more than one dt element for each name; a duplicated term usually means two descriptions were meant to share one dt. | | [`a11y/pattern-title`](/rules/a11y/pattern-title) | 🔵 info | When an input has a pattern, the spec says authors should include a title describing the expected format; without it a failed submit tells the user only that the value is wrong. | | [`a11y/require-datetime`](/rules/a11y/require-datetime) | 🔵 info | A time element's text should be machine-readable, or a datetime attribute should supply the machine-readable value. | | [`a11y/unverified-id-ref`](/rules/a11y/unverified-id-ref) | 🔵 info | Opt-in: flags id references that cannot be verified on routes whose composition is not fully resolved. | | [`a11y/use-list`](/rules/a11y/use-list) | 🔵 info | A bullet character typed into plain text should be a real list element instead. | {/* rules-index:end */} See [Configuration](/guides/configuration) to change a rule's severity or turn it off.