HTML <rb> Tag

What You’ll Learn

The <rb> tag once marked the base text in ruby annotations for East Asian typography. This guide explains its historical role, deprecated status, and the modern ruby, rt, and rp elements beginners should use instead.

What Is the <rb> Tag?

The <rb> tag, short for “ruby base,” was used with the <ruby> element to denote the base text component of a ruby annotation. Ruby annotations add pronunciation or translation hints above or beside characters — common in Japanese, Chinese, and Korean typography.

Learn rb only to understand legacy markup. For ruby annotations today, use ruby with rt and optional rp fallback.

🚫 Deprecated Status

The <rb> tag is deprecated in HTML5 and is not supported for use in modern web development practices. Instead, the <ruby> element is recommended for defining ruby annotations, with the rb functionality implicitly applied to the base text placed directly inside ruby.

• Removed from the HTML5 ruby annotation model.
• Base text no longer needs a separate wrapper element.
• Using rb may cause inconsistent parsing across browsers.
• Replace with ruby, rt, and rp in all new projects.

📝 Syntax

As <rb> is deprecated, understand its historical syntax within older HTML versions:

<rb>Your Ruby Base Text</rb>

Modern Replacement Syntax

<ruby>
  漢 <rt>kan</rt>
</ruby>

Syntax Rules

• Do not wrap base characters in rb in new documents.
• Put base text and rt annotations inside a single ruby element.
• Use rp before and after rt for fallback parentheses.
• Set lang on the page or element for correct typography.

⚖️ <rb> vs <ruby>

📚 Common Use Cases

The <rb> tag was primarily employed in conjunction with the <ruby> element to provide ruby annotations in East Asian typography. However, due to its deprecated status, its usage is not recommended in modern HTML development.

Examples Gallery

Practice the modern replacements for deprecated rb: ruby, rt, and rp.

<ruby>漢<rt>kan</rt></ruby>

<ruby>東京<rt>とうきょう</rt></ruby>

<ruby>
  漢 <rp>(</rp><rt>kan</rt><rp>)</rp>
</ruby>

♿ Accessibility

• Use ruby for annotations — Semantic markup helps assistive technology identify base text and readings.
• Skip deprecated rb — Modern parsers expect base text directly in ruby.
• Set lang attribute — Declare Japanese, Chinese, or Korean for correct pronunciation hints.
• Provide context in prose — Explain unfamiliar characters when teaching language content.

💡 Best Practices

As rb is deprecated, the best practice is to avoid its usage altogether. Instead, utilize the ruby element for defining ruby annotations in compliance with modern HTML standards.