The HTML aria-modal attribute
The aria-modal="true" attribute tells assistive technology that everything behind a dialog is inert, so it should keep the user inside the dialog. Set it on the element with role="dialog" or role="alertdialog". The native <dialog> with showModal() manages this for you.
Overview
The aria-modal attribute indicates that a dialog blocks interaction with the rest of the page.
It is a widget state — a condition that can change as the user interacts. Because ARIA does nothing on its own, you must update this value in JavaScript every time the underlying state changes; a stale state is worse than none. And wherever a native element already expresses the same thing (a checkbox's checked state, the disabled attribute, a <details>'s open state), use that instead.
Like all ARIA, aria-modal changes only the accessibility tree — what assistive technology perceives — never the element's behavior or appearance. The first rule of ARIA applies: if a native HTML element or attribute conveys this, use that instead, and only reach for ARIA when nothing native fits.
Syntax
<div role="dialog" aria-modal="true" aria-labelledby="t"> … </div>Values
| Value |
|---|
| true | false |
Example
<div role="dialog" aria-modal="true" aria-labelledby="dlg-title">
<h2 id="dlg-title">Confirm</h2> …
</div>Best practices
- Follow the first rule of ARIA — use a native HTML element or attribute that conveys this where one exists, rather than adding ARIA.
- Update the value in JavaScript whenever the state changes — keep it in sync with reality.
- Use the matching native state where one exists (a checkbox's
checked, thedisabledattribute, a <details>'s open state) instead of the ARIA version. - Set it only on an element whose role actually supports this state.