Axe Core Guide

An image map consists of a single image with numerous clickable sections. Because screen readers cannot translate graphics into text, an image map, like all images, must contain alternative text for each of the distinct clickable parts, as well as for the larger image itself.

In the absence of alternative text, screen readers often announce the image’s filename. Filenames do not accurately describe images and are therefore inconvenient for screen reader users.

What this Accessibility Rule Checks

Ensures that image map area elements have alternative text.

Makes certain that <input type="image"> elements have alternative text.

Screen reader users will not understand the function of a <input type="image"> button unless equivalent wording is provided. Even if the image merely contains text, alternative text is required because a screen reader cannot interpret images of words into output.

Simply typing text adjacent to the form element will not result in a true label. Screen readers, for example, require labels in code that can be determined automatically.

Some screen readers are configured to estimate the label based on the surrounding text, however this method is not foolproof and might cause confusion if the screen reader guesses incorrectly.

What this Accessibility Rule Checks

Ensures that each <input type="image"> has a name that can be found.

A label element with a programmatic association must be included for each select element.

To make forms accessible, they must have clear form labels. Even if a form element isn’t programmatically named, sighted users can usually tell what it’s for when they see checkboxes, radio buttons, input fields, etc. To identify form fields, screen reader users need clear form labels. All form elements should have labels to remove confusion and make the product more accessible.

Screen reader users are in the dark about the expected input data when form elements lack labels. Without a defined label connection (or redundant text acting as a label), screen readers cannot automatically determine information about input items.

What this Accessibility Rule Checks

ensures that each select element has a label that is associated with it programmatically.

Not all ARIA role-attribute combinations are valid. This rule ensures that each role has the required qualities.

Using ARIA attributes in roles where they are not permitted can impair web page accessibility. Using an improper role-attribute combination will have no effect on application accessibility at best and may trigger behavior that blocks accessibility for entire areas of an application at worst.

When ARIA attributes are used on HTML elements that do not conform to WAI-ARIA 1.1, they interfere with the semantics of the elements, causing assistive technology products to display nonsensical user interface (UI) information that does not represent the document’s true UI.

What this Accessibility Rule Checks

Checks that each element with an ARIA role is using only the ARIA attributes that are permitted for that role.

aria-braille attributes must have a non-braille equivalent.

WAI-ARIA requires that the aria-braillelabel attribute is only ever used on elements with an accessible name, such as from aria-label. Similarly, aria-brailleroledescription is required to only ever be used on elements with aria-roledescription.

ARIA braille attributes were introduced to allow adjusting how labels and role descriptions are rendered on a braille display. They cannot be the only attribute providing a label, or a role description. When used without a corresponding label or role description ARIA says to ignore these attributes, although this may not happen consistently in screen readers and other assistive technologies.

How to Fix this Issue

• The aria-braillelabel or aria-brailleroledescription attribute may have been placed on the wrong element, such as a parent or child of the correct element. The attribute should be put on a different element.
• The element with aria-braillelabel attribute needs an aria-label attribute or other attribute that gives it an accessible name.
• The element with aria-brailleroledescription attribute needs a aria-roledescription attribute.
• The aria-braillelabel or aria-brailleroledescription attribute serves no function and should be removed.

What this Accessibility Rule Checks

Checks that aria-braillelabel is only used on elements with a non-empty label, and that aria-brailleroledescription is only used on elements with a non-empty aria-roledescription.

Elements with aria-hidden must not contain focusable elements.

Using the property aria-hidden="true" on an element removes the element and all of its child nodes from the accessibility API, rendering the element fully unavailable to screen readers and other assistive technology.

aria-hidden may be used with extreme discretion to hide visibly displayed content from assistive technologies if the act of hiding this content is meant to enhance the experience of assistive technology users by reducing redundant or superfluous content.

If aria-hidden is employed to hide material from screen readers, the same or equal meaning and functionality must be made available to assistive technologies.

Using aria-hidden="false" on content that is a descendant of an element that is hidden using aria-hidden="true" will not reveal that content to the accessibility API, nor will it be accessible to screen readers or other assistive technology.

The rule applies to any element whose aria-hidden attribute value is true.

By adding aria-hidden="true" to an element, authors assure that assistive technologies will disregard the element. This can be used to hide aesthetic elements, such as icon typefaces, that are not intended to be read by assistive technologies.

A focusable element with aria-hidden="true" is disregarded as part of the reading order, but is still part of the focus order, making it unclear if it is visible or hidden.

What this Accessibility Rule Checks

For all user interface components, including form elements, links, and script-generated components, the name and role can be identified programmatically; user-specified states, properties, and values can be set programmatically; and user agents, including assistive technologies, are notified of changes.

ARIA widget roles must contain attributes describing the widget’s state or properties.

ARIA widget roles necessitate additional properties describing the widget’s state. If a needed attribute is missing, the widget’s status is not conveyed to users of screen readers.

Some roles function as composite user interface widgets. As such, they serve as containers that manage the widgets they contain. When an object inherits from several ancestors and one ancestor indicates support for a property and another says the property is required, the property becomes required on the inheriting object. In some circumstances, default values are sufficient to meet ARIA attribute requirements.

When required state and property attributes for specific roles (and subclass roles) are missing, screen readers may be unable to communicate the element’s role definition to the user.

What this Accessibility Rule Checks

Checks all elements with the role attribute to ensure that all necessary attributes are defined.

Some ARIA role values in parent elements must contain specific child elements and role values in order to execute the intended accessibility function.

WAI-ARIA outlines specifically, for each role, which child and parent roles are permitted and/or required. ARIA roles lacking needed child roles will not be able to execute the desired accessibility functions.

The user’s context must be communicated by assistive technology. In a treeitem, for instance, it is essential to know the parent (container), item, and siblings in the folder. This is possible in two ways:

• Code order or DOM: The context required is frequently evident from the code order or DOM.
• ARIA: ARIA (such as aria-owns) can be used to provide relationships when the hierarchy differs from the code structure or the DOM tree.

What this Accessibility Rule Checks

Checks each element containing a WAI-ARIA role for the presence of all requisite child roles.

Certain ARIA roles must be enclosed by specific parent roles in order to carry out their intended accessibility functions.

WAI-ARIA outlines specifically, for each role, which child and parent roles are permitted and/or required. Elements with ARIA role values that lack needed parent element role values will prevent assistive technology from functioning as the developer intended.

When it is necessary to convey context to a user of assistive technology in the form of hierarchy (for example, the importance of a parent container, item, or sibling in a folder tree), and the hierarchy is not the same as the code structure or DOM tree, it is impossible to provide relationship information without using ARIA role parent elements.

What this Accessibility Rule Checks

Checks each WAI-ARIA role-containing element to confirm that all required parent roles are present.

ARIA role values must be assigned valid values. Role values must be appropriately written, correlate to existing ARIA role values, and not be abstract roles in order to correctly display the element’s purpose.

Assistive technologies do not read elements with erroneous ARIA role values as intended by the developer.

When screen readers and other assistive devices do not know the function of each element on a web page, they are unable to interact with or communicate the function to the user. When a role value is invalid, an element’s characteristics, properties, and ways of transmitting information to and/or from the user can be communicated via assistive technologies.

What this Accessibility Rule Checks

Examines each element containing the WAI-ARIA role property to check that its value is valid.