Accessibility Checking for Large Sites
Rocket Validator automatically scans your sites for accessibility issues using the axe-core a11y engine,
hosted on our own servers and integrated into our web crawler.
You don't need to buy an additional license, the axe-core scanner comes included in your Pro account at Rocket Validator.
Accessibility Rules checked by Rocket Validator
Rocket Validator integrates axe-core version 4.1, which currently checks 90 accessibility rules, into an automated web site scanner.
These are the rules that will be checked on every page of your sites. Click on each to get an extended description.
All accesskey attribute values in a document must be unique. Put another way, accesskeys must not be repeated to prevent unexpected effects for keyboard users.
An image map is a single image with many clickable areas. Like all images, an image map must have alternate text for each of the different clickable areas, as well as for the larger image itself, since screen readers have no way of translating graphics into text.
Data table markup can be tedious and confusing. Markup tables semantically and with the correct header structure. Screen readers have features to ease table navigation, but tables must be marked up accurately for these features to work correctly.
Data table markup can be tedious and confusing. Markup tables semantically and with the correct header structure. Screen readers have features to ease table navigation, but tables must be marked up accurately for these features to work correctly.
Data table markup can be tedious and confusing. Tables must be marked up done semantically and with the correct header structure. Screen readers have features to ease table navigation, but tables must be marked up accurately for these features to work correctly.
It is best practice to contain all content excepting skip links, within distinct regions such as the header, nav, main, and footer.
ARIA attributes starting with aria- must have valid names. Referring to a misspelled attribute or to one that does not exist will result in an invalid attribute and thus failure of this rule.
ARIA attributes starting with aria- must contain valid values. These values must be spelled correctly and correspond to values that make sense for a particular attribute in order to perform the intended accessibility function.
ARIA command elements must have discernible text that clearly describes the destination, purpose, function, or action for screen reader users.
Aria dialog elements must have discernible text that clearly describes the destination, purpose, function, or action for screen reader users.
This rule checks aria-hidden elements do not contain focusable elements.
Document content is not accessible to assistive technology if <body aria-hidden="true">.
Ensures every ARIA input field has an accessible name.
Aria meter elements must have discernible text that clearly describes the destination, purpose, function, or action for screen reader users.
Aria progressbar elements must have discernible text that clearly describes the destination, purpose, function, or action for screen reader users.
Values assigned to WAI-ARIA role attributes must be valid. This means values must be spelled correctly, correspond to existing ARIA role values, and must not be abstract roles in order to correctly expose the purpose of the element.
Values assigned to ARIA role values must be valid. Role values must be spelled correctly, correspond to existing ARIA role values, and must not be abstract roles to correctly expose the purpose of the element.
Ensures every ARIA toggle field has an accessible name.
Aria tooltip elements must have discernible text that clearly describes the destination, purpose, function, or action for screen reader users.
Aria treeitem elements must have discernible text that clearly describes the destination, purpose, function, or action for screen reader users.
Ensures <video> or <audio> elements do not autoplay audio for more than three seconds without a control mechanism to stop or mute the audio.
The purpose for each common input field that collects an individual's personal data is programmatically defined based on the list of 53 Input Purposes for User Interface Components. The autocomplete attribute values must be valid and correctly applied for screen readers to function correctly.
Banner landmark must not be contained in another landmark.
Styled p elements must not be used to represent headings because the structure of the document cannot otherwise be determined by screen reader users.
Buttons must have discernible text that clearly describes the destination, purpose, function, or action for screen reader users.
The input-button-name rule separates functionality from the button-name rule to ensure that input buttons have discernible text; advise relevant to input button names was incorrect for button elements.
Certain ARIA roles must be contained by particular parent roles in order to perform the intended accessibility functions.
Some ARIA parent role values applied to elements must contain specific child elements and role values to perform intended accessibility function.
Ensures the complementary landmark or aside is at top level
Contentinfo landmark must be at top level.
The screen orientation (e.g. portrait or landscape) of mobile applications should not be locked in one mode. Users should be able to change the orientation of their device between portrait and landscape with the page adjusting accordingly in order to remain understandable. Also, when opening a page, it should display in the user’s current orientation.
Data table markup can be tedious and confusing. Screen readers have some features to ease table navigation, but tables must be marked up accurately for these features to work correctly. Some tables use cells with a colspan element to visually indicate a caption, instead of using an actual caption element.
The HTML document must have a title element to provide users with an overview of its content, and when present, it must not be empty.
role="img" have an alternative text
Ensures elements marked role="img" elements have alternate text.
User input elements must have appropriate roles, whether native HTML or a custom widget, to convey to screen reader users their meaning when landed on and given focus. If a custom widget, appropriate ARIA role values must be used instead of abstract roles to correctly expose the purpose of the element.
Not all ARIA role-attribute combinations are valid. This Rule checks that each role is supplied with allowed attributes.
A tabindex attribute must never have a value greater than 0 to prevent an unexpected tab order that can give the appearance of skipping some elements entirely.
Ensures elements which are marked to be removed from the accessibility tree are in fact removed.
It is a best practice to ensure that there is only one main landmark to navigate to the primary content of the page and that if the page contains iframe elements, each should either contain no landmarks, or just a single landmark.
Ensure that links with the same accessible name serve a similar purpose.
Ensures form field does not have multiple labels.
Each form element must have a programmatically associated label element.
Form <input> elements may be given a title using the title or aria-describedby attributes (but not both). These attributes are used to provide additional information such as a hint.
All frame or iframe elements in the document must have a unique title to describe their contents to screen reader users.
All frame or iframe elements in the document must have a title that is not empty to describe their contents to screen reader users.
Headings must be in a valid logical order, meaning h1 through h6 element tags must appear in a sequentially-descending order.
When at least one heading element (marked by <h1> through <h6>) is present, it is a best practice to ensure it contains content.
Informs users about hidden content that cannot be analyzed for accessibility violations.
The value assigned to active ID attributes on focusable elements must be unique to prevent the second instance from being overlooked by assistive technology. Put another way, active ID attributes may not be used more than once on focusable elements in the same document; focusable active elements require unique IDs for assistive technology to distinguish one element from another.
The value assigned to an ID attribute must be unique to prevent the second instance from being overlooked by assistive technology. Put another way; ID attributes may not be used more than once in the same document to differentiate each element from another.
The value assigned to an ARIA ID must be unique to prevent the second instance from being overlooked by assistive technology. Put another way; ARIA ID values may not be used more than once in the same document to differentiate each element from another.
Ensures <input type="image"> elements have alternate text.
All images must have alternate text to convey their purpose and meaning to screen reader users.
Ensure that text spacing set through style attributes can be adjusted with custom stylesheets.
Ensures input buttons have discernible text.
The input-button-name rule separates functionality from the button-name rule to ensure that input buttons have discernible text; advise relevant to input button names was incorrect for button elements.
Interactive elements labeled through their content must have their visible label as part of their accessible name
The language specified in the HTML document must be one of the valid languages to ensure text is pronounced correctly for screen reader users.
Ensures users who cannot distinguish between colors can tell when text is a link by verifying the link has either a distinct style that does not rely on color or has a contrast difference of greater than 3:1 (which alerts you that manual testing is required).
Link text and alternate text for images, when used as links, must be discernible by a screen reader, must not have a duplicate label, and must be focusable.
This rule requires that no blink elements are present. Flashing text can be difficult to read and blinking objects can be difficult to activate. The associated automated check finds the presence of all blink elements so that they can be removed.
Definition lists (dl) must contain only properly-ordered dt and dd groups, script or template elements.
Definition list items (dt and/or dd) must be wrapped in parent dl elements to be valid. This enables screen reader users to understand the proper hierarchy of information in the list.
The HTML document element must contain a valid lang attribute or must correspond to a valid lang code for multilingual screen reader users who may prefer a language other than the default.
The HTML document must contain a valid lang attribute or must correspond to a valid lang code for multilingual screen reader users who may prefer a language other than the default.
The HTML document must contain a valid lang attribute or must correspond to a valid lang code for multilingual screen reader users who may prefer a language other than the default. The xml:lang attribute value, if included on the html element, must duplicate the value of the lang exactly.
All list items (li) must be contained within ul or ol parent elements.
<marquee> elements must not be present because they are deprecated, increase difficulty for users with limited dexterity, and are distracting for users with cognitive or attention deficits.
All embedded objects must have text alternatives to be read out to screen reader users.
Lists must be marked up correctly, meaning they must not contain content elements other than li elements.
It is a best practice to ensure the main landmark is not contained within another landmark. All content should be contained within distinct regions such as the header (role="banner"), content (role="main"), and footer (role="contentinfo").
Ensures that the page, or at least one of its frames, contains an h1 element that appears before the start of the main content to allow screen reader users to use keyboard shortcuts to navigate the heading structure instead of wasting time listening to more of the web page to understand its structure.
Each page must have a main landmark to provide a mechanism to bypass repeated blocks of content or interface elements (like header and navigation) and quickly arrive at the main content.
It is a best practice to ensure that there is only one main landmark to navigate to the primary content of the page and that if the page contains iframe elements, each should either contain no landmarks, or just a single landmark.
Ensures the page has at most one banner landmark.
Ensures the page has at most one contentinfo landmark.
ARIA widget roles must have appropriate attributes describing the state or properties of the widget.
The scope attribute must be used correctly on tables in accordance with either HTML4 or HTML5 specifications to enable efficient table navigation for screen reader users.
Each select element must have a programmatically associated label element.
The document contains an image map that is server-side instead of client-side.
Ensures SVG elements with an <img>, graphics-document or graphics-symbol role have an accessible text alternative.
All text elements must have sufficient contrast between text in the foreground and background colors behind it in accordance with WCAG 2 AA contrast ratio thresholds.
When button and link text repeats in a alt attribute value, screen reader users hear the same information twice, which renders the alt text meaningless and confusing.
Data table markup can be tedious and confusing. Make sure the caption and summary table attributes are not identical. Screen readers have some features to manage table navigation, but tables must be marked up accurately for these features to work correctly.
The page must have a link at the top before the navigation that allows users to skip lengthy navigation and proceed to a page's main content to save time.
The document must not use <meta http-equiv="refresh"> because it can prevent control over when the refresh occurs for users with disabilities.
Ensures that the aria-roledescription attribute is only used on elements with an implicit or explicit role values.
The document must not use the user-scalable="no" parameter in the <meta name="viewport"> element because it disables text scaling and zooming which is essential to users with low vision.
The document must not use the user-scalable="no" parameter in the <meta name="viewport"> element because it disables text scaling and zooming which is essential to users with low vision.