The HTML <bdi> Element (or Bi-Directional Isolation Element) isolates a span of text that might be formatted in a different direction from other text outside it.

This element is useful when embedding text with an unknown directionality, from a database for example, inside text with a fixed directionality.

Though the same visual effect can be achieved using the CSS rule unicode-bidi: isolate on a <span> or another text-formatting element, the semantic meaning is only conveyed by the <bdi> element. Especially, browsers are allowed to ignore CSS styling. In such a case, the text would still be correctly displayed using the HTML element, but will become garbage when using the CSS styling to convey semantic.

Content categories Flow content, phrasing content, palpable content.
Permitted content Phrasing content.
Tag omission None, both the starting and ending tag are mandatory.
Permitted parent elements Any element that accepts phrasing content.
DOM interface HTMLElement


Like all other HTML elements, this element has the global attributes, with a slight semantic difference: the dir attribute is not inherited. If not set, its default value is the auto which let the browser decide the direction based on the element's content.


<p dir="ltr">This arabic word <bdi>ARABIC_PLACEHOLDER</bdi> is automatically displayed right-to-left.</p>


This arabic word REDLOHECALP_CIBARA is automatically displayed right-to-left.


Specification Status Comment
WHATWG HTML Living Standard
The definition of '<bdi>' in that specification.
Living Standard  
The definition of '<bdi>' in that specification.

Browser compatibility

Feature Chrome Firefox (Gecko) Internet Explorer Opera Safari
Basic support 16 10.0 (10.0) Not supported Not supported Not supported
Feature Android Firefox Mobile (Gecko) IE Mobile Opera Mobile Safari Mobile
Basic support Not supported 10.0 (10.0) Not supported Not supported Not supported

See also

Document Tags and Contributors

 Contributors to this page: Sebastianz, kscarfone, teoli, zajac, Sheppy, petertosirisuk, ethertank, cers, avsaro
 Last updated by: Sebastianz,