Accessible description

An accessible description is the description of a user interface element that provides additional information to help users of assistive technology understand the UI element and its context. It is a text description associated with an HTML element that provides users of assistive technology with a description for the element beyond what is provided by the element's accessible name.

An element's accessible description is part of the accessibility tree that makes web content available to screen readers and other assistive technologies, which, in turn, make that content available to the users of those technologies.

The accessible description for a <table> is its first <caption>, for the <figure>, is the <figcaption>, for the <summary>, is the content of the <details> it is nested in, and for the button <input> elements, it is the value attribute's value, unless the element also has a aria-describedby or aria-description attribute, which takes precedence.

For other elements, the description needs to be programmatically associated with the related element. In these cases, the accessible description is provided by the aria-describedby attribute, aria-description attribute, or the title attribute, if the title would not otherwise also be the accessible name for that element, in that order of precedence.

Descriptions are reduced to text strings. For example, if an element's aria-describedby attribute value is the id of an HTML <img>, the description is the description of the image (usually the image's alt attribute).

You can inspect the accessible description for any element on your page: look at your browser's developer tools' accessibility tab, which provides the accessibility information for the currently selected element.