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Summary
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 |
Attributes
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.
Example
<p dir="ltr">This arabic word <bdi>ARABIC_PLACEHOLDER</bdi> is automatically displayed right-to-left.</p>
Result
This arabic word REDLOHECALP_CIBARA is automatically displayed right-to-left.
Specifications
| Specification | Status | Comment |
|---|---|---|
| WHATWG HTML Living Standard The definition of '<bdi>' in that specification. |
Living Standard | |
| HTML5 The definition of '<bdi>' in that specification. |
Recommendation |
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
- Related HTML element:
<bdo> - Related HTML properties:
direction,unicode-bidi