<rb>: The Ruby Base element

Deprecated: This feature is no longer recommended. Though some browsers might still support it, it may have already been removed from the relevant web standards, may be in the process of being dropped, or may only be kept for compatibility purposes. Avoid using it, and update existing code if possible; see the compatibility table at the bottom of this page to guide your decision. Be aware that this feature may cease to work at any time.

The <rb> HTML element is used to delimit the base text component of a <ruby> annotation, i.e. the text that is being annotated. One <rb> element should wrap each separate atomic segment of the base text.

Content categories	None.
Permitted content	As a child of a `<ruby>` element.
Tag omission	The end tag can be omitted if the element is immediately followed by an `<rt>`, `<rtc>`, or `<rp>` element or another `<rb>` element, or if there is no more content in the parent element.
Permitted parents	A `<ruby>` element.
Permitted ARIA roles	Any
DOM interface	`HTMLElement`

Attributes

This element only includes the global attributes.

Usage notes

Ruby annotations are for showing pronunciation of East Asian characters, like using Japanese furigana or Taiwanese bopomofo characters. The <rb> element is used to separate out each segment of the ruby base text.
Even though <rb> is not an empty element, it is common to just include the opening tag of each element in the source code, so that the ruby markup is less complex and easier to read. The browser can then fill in the full element in the rendered version.
You need to include one <rt> element for each base segment/<rb> element that you want to annotate.

Examples

Using rb

In this example, we provide an annotation for the original character equivalent of "Kanji":

<ruby>
  <rb>漢<rb>字
  <rp>(</rp><rt>kan<rt>ji<rp>)</rp>
</ruby>

Note how we've included two <rb> elements, to delimit the two separate parts of the ruby base text. The annotation on the other hand is delimited by two <rt> elements.

Separate annotations

Note that we could also write this example with the two base text parts annotated completely separately. In this case we don't need to include <rb> elements:

<ruby>
  漢 <rp>(</rp><rt>Kan</rt><rp>)</rp>
  字 <rp>(</rp><rt>ji</rt><rp>)</rp>
</ruby>

See the article about the <ruby> element for further examples.

Specifications

Specification
HTML Standard (HTML) # rb

Browser compatibility

	Desktop						Mobile
	Chrome	Edge	Firefox	Internet Explorer	Opera	Safari	WebView Android	Chrome Android	Firefox for Android	Opera Android	Safari on IOS	Samsung Internet
`rb`	5 Blink has support for parsing the `rb` element, but not for rendering `rb` content as expected.	79 Blink has support for parsing the `rb` element, but not for rendering `rb` content as expected.	38	5	15 Blink has support for parsing the `rb` element, but not for rendering `rb` content as expected.	5 Safari has support for parsing the `rb` element, but not for rendering `rb` content as expected.	37 Blink has support for parsing the `rb` element, but not for rendering `rb` content as expected.	18 Blink has support for parsing the `rb` element, but not for rendering `rb` content as expected.	38	14 Blink has support for parsing the `rb` element, but not for rendering `rb` content as expected.	Yes Safari has support for parsing the `rb` element, but not for rendering `rb` content as expected.	Yes Blink has support for parsing the `rb` element, but not for rendering `rb` content as expected.