HTML: the obsolete `acronym` element

The <acronym> element was once used for acronyms, but it is obsolete in modern HTML. Use <abbr> instead.

What you will learn

Why <acronym> should not be used in new HTML
How to replace it with <abbr> and title
How to explain shortened terms without relying only on a tooltip

What changed?

Older HTML specifications distinguished acronyms from other abbreviations. HTML5 removed that distinction and made <abbr> the current element for both kinds of shortened terms.

Use `abbr` instead

<p>
  <abbr title="World Wide Web Consortium">W3C</abbr> publishes web standards.
</p>

The title value provides the expanded form in supporting browsers. When the full name is important, also write it visibly in the surrounding text so that every reader can find it.

Updating old code

<!-- Old -->
<acronym title="World Wide Web Consortium">W3C</acronym>

<!-- Current -->
<abbr title="World Wide Web Consortium">W3C</abbr>

The old element may still render in some browsers, but rendering is not a reason to keep obsolete markup. Update it when maintaining the page and test the visible result and assistive technology behavior.

Common mistakes

Adding new <acronym> markup because old examples use it.
Putting a long paragraph in title instead of a short expanded name.
Assuming that every reader can discover a tooltip.