Axe Core Guide

Markup for data tables can be tedious and perplexing. Tables must be semantically marked up and have the proper header structure. Table navigation is made easier by features in screen readers, but for these capabilities to function properly, the tables must be precisely marked up.

Tables are announced in a certain way by screen readers. The potential for unclear or erroneous screen reader output exists when tables are not properly marked up.

Screen reader users are unable to correctly understand the relationships between the cells and their contents visually when tables are not adequately structured and marked up semantically.

What this Accessibility Rule Checks

Verifies the correct header structure and semantic markup of data tables.

Since screen reader users cannot otherwise determine the structure of the document, styled p components must not be utilized to represent headings.

The fundamental goal of headers is to communicate the page’s organizational structure. Using varied text sizes allows sighted readers to see the structure. However, heading components must be marked up properly for screen reader users.

When header components are used correctly, both sighted and screen reader users will find it much simpler to traverse the page.

Users of screen readers can navigate between headings in the same manner that sighted users might skim a page to gain a sense of its contents. Users, especially those who use screen readers, can save a ton of time and stress by using well-written, logically-arranged headings.

Headings serve to explain the organization of the webpage, not only to draw attention to key text. They must be succinct, distinct, and numbered h1 through h6 in hierarchical sequence. For screen reader users, headers are a useful tool because of all of these characteristics.

Users of screen readers can navigate between headings in the same manner that sighted users might skim a page to gain a sense of its contents. Users, especially those who use screen readers, can save a ton of time and stress by using well-written, logically-arranged headings.

Due to the fact that search engines use headings when filtering, arranging, and showing results, headers offer advantages beyond just making a page more accessible. Making your website more searchable is another benefit of making it more accessible.

What this Accessibility Rule Checks

Verifies that paragraph components are not given the appearance of headers by using italic, bold, or font size.

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.

For screen reader users, buttons must include recognizable text that specifies the destination, purpose, function, or action.

Users of screen readers are unable to determine the function of elements with the roles role="link", role="button", and role="menuitem" that lack an accessible name.

What this Accessibility Rule Checks

Verifies that each button has a distinguishable, accessible label.

Each page must have a main landmark to allow users to rapidly traverse repetitive blocks of material or interface elements (such as the header and navigation) and get the primary content.

Due to the fact that websites frequently display secondary, repetitive content on several pages (such as navigation links, heading graphics, and advertising frames), keyboard-only users benefit from faster, more direct access to a page’s principal content. This saves keystrokes and reduces physical discomfort.

It is more difficult and time-consuming for users who cannot use a mouse to navigate using the keyboard if the interface does not provide features to facilitate keyboard navigation. To activate a link in the middle of a web page, for instance, a keyboard user may have to browse through a significant number of links and buttons in the page’s header and primary navigation.

Extremely motor-impaired users may require several minutes to browse through all of these pieces, which can cause to tiredness and potential physical pain for some users. Even users with less severe limitations will require more time than users with a mouse, who can click on the desired link in less than a second.

What this Accessibility Rule Checks

Checks for the presence of at least one of the following features:

• an internal skip link
• a header
• a geographical landmark

When used in a document, the frame or iframe element’s title attribute must not be empty in order to provide context for users of screen reader software.

Users of screen readers depend on the title of a frame to describe its contents. If the HTML for a frame or iframe element lacks a title attribute, navigating within the element can be a frustrating and time-consuming experience for users of this technology.

Users of screen readers can see a list of the frames on a page and their respective titles. Providing each frame with a distinct, descriptive label facilitates easy navigation. Without titles, it’s easy to get lost trying to jump from one frame to the next. Screen readers will instead provide information like “frame,” “JavaScript,” the filename, or the URL if no title is provided. This data is unlikely to be useful in most situations.

What this Accessibility Rule Checks

Make sure the title attribute of every iframe and frame element is both distinct and not empty.

To express their purpose and meaning to screen reader users, all images must include alternative text.

Even if the image just contains text, screen readers have no way of translating it into words that are read to the user. As a result, photos must have concise, descriptive alt text so that screen reader users grasp the image’s contents and purpose.

If you can’t see, all visual information, such as photographs, is meaningless unless a digital text equivalent is provided so that screen readers may translate that text into either sound or braille. People with limited eyesight or colorblindness experience the same phenomenon to varied degrees.

Screen readers cannot translate an image into speech or braille to make it available by sound or touch if you do not provide a suitable alternative that works for their available sensory modalities, such as making an image accessible by providing a digital text description.

What this Accessibility Rule Checks

Ensures that all <image> elements have alternative text and either role="presentation" or role="none" (ARIA 1.1).

Ensures that input buttons have legible text.

Without an accessible name, screen reader users cannot determine the purpose of a input type="button".

Without a discernible and accessible name, screen reader users cannot grasp the purpose of an image. A title for a photograph may just convey advisory information about the image. When used as a control, unnamed actionable visual images such as buttons have no clear definition of the destination, purpose, function, or action for the non-text material.

What this Accessibility Rule Checks

The text on input buttons must be readable.

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.

The visible label of interactive items labeled through their content must be included in their accessible name.

This rule applies to any element with the following attributes:

• a semantic role that is a widget that supports name from content,
• visible text, and
• an aria-label or aria-labelledby attribute.

button, checkbox, gridcell, link, menuitem, menuitemcheckbox, menuitemradio, option, radio, searchbox, switch, tab, and treeitem are widget roles that support name from content.

The whole visible text content of the target element either matches its accessible name or is contained within it.

Leading and trailing whitespace and case sensitivity differences should be disregarded.

Users using speech input can interact with a web page by saying the visible text labels of menus, links, and buttons.

Voice input users are confused when they utter a visible text label, but the speech command does not work since the accessible (programmatic) name of the component does not match the visible label. When a user interface component contains a visible text label — whether the label is actual text or a picture of text — that text must also appear in the component’s accessible (programmatic) name. When the visual label and accessible (programmatic) name for interactive components are synchronized, users using speech input can engage with those components successfully.

What this Accessibility Rule Checks

For any user interface element with a visible text label, the accessible name must match (or include) the label’s visible text.