<abbr>: The Abbreviation element

The <abbr> HTML element represents an abbreviation or acronym; the optional title attribute can provide an expansion or description for the abbreviation. If present, title must contain this full description and nothing else.

This element only supports the global attributes. The title attribute has a specific semantic meaning when used with the <abbr> element; it must contain a full human-readable description or expansion of the abbreviation. This text is often presented by browsers as a tooltip when the mouse cursor is hovered over the element.

Each <abbr> element you use is independent from all others; providing a title for one does not automatically attach the same expansion text to others with the same content text.

It's certainly not required that all abbreviations be marked up using <abbr>. There are, though, a few cases where it's helpful to do so:

• When an abbreviation is used and you want to provide an expansion or definition outside the flow of the document's content, use <abbr> with an appropriate title.
• To define an abbreviation which may be unfamiliar to the reader, present the term using <abbr> and either a title attribute or inline text providing the definition.
• When an abbreviation's presence in the text needs to be semantically noted, the <abbr> element is useful. This can be used, in turn, for styling or scripting purposes.
• You can use <abbr> in concert with <dfn> to establish definitions for terms which are abbreviations or acronyms. See the example Defining an abbreviation below.

In languages with grammatical number (that is, languages where the number of items affects the grammar of a sentence), use the same grammatical number in your title attribute as inside your <abbr> element. This is especially important in languages with more than two numbers, such as Arabic, but is also relevant in English.

The purpose of this element is purely for the convenience of the author and all browsers display it inline (display: inline) by default, though its default styling varies from one browser to another:

• Some browsers, like Internet Explorer, do not style it differently than a <span> element.
• Opera, Firefox, and some others add a dotted underline to the content of the element.
• A few browsers not only add a dotted underline, but also put it in small caps; to avoid this styling, adding something like font-variant: none in the CSS takes care of this case.

To mark up an abbreviation without providing an expansion or description, use <abbr> without any attributes, as seen in this example.

HTML

<p>Using <abbr>HTML</abbr> is fun and easy!</p>

Result

You can use CSS to set a custom style to be used for abbreviations, as seen in this simple example.

HTML

<p>Using <abbr>CSS</abbr>, you can style your abbreviations!</p>

CSS

abbr {
  font-variant: all-small-caps;
}

Result

Adding a title attribute lets you provide an expansion or definition for the abbreviation or acronym.

HTML

<p>Ashok's joke made me <abbr title="Laugh Out Loud">LOL</abbr> big
time.</p>

Result

You can use <abbr> in tandem with <dfn> to more formally define an abbreviation, as shown here.

HTML

<p><dfn id="html"><abbr title="HyperText Markup Language">HTML</abbr>
</dfn> is a markup language used to create the semantics and structure
of a web page.</p>

<p>A <dfn id="spec">Specification</dfn>
(<abbr title="Specification">spec</abbr>) is a document that outlines
in detail how a technology or API is intended to function and how it is
accessed.</p>

Result

Spelling out the acronym or abbreviation in full the first time it is used on a page is beneficial for helping people understand it, especially if the content is technical or industry jargon.

Example

<p>JavaScript Object Notation (<abbr>JSON</abbr>) is a lightweight data-interchange format.</p>

This is especially helpful for people who are unfamiliar with the terminology or concepts discussed in the content, people who are new to the language, and people with cognitive concerns.

• Using the <abbr> element