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The :only-of-type CSS pseudo-class represents an element that has no siblings of the same type.

/* Selects each <p>, but only if it is the */
/* only <p> element inside its parent */
p:only-of-type {
  background-color: lime;
}

Note: As originally defined, the selected element had to have a parent. Beginning with Selectors Level 4, this is no longer required.

Syntax

:only-of-type

Example

HTML

<main>
  <div>I am `div` #1.</div>
  <p>I am the only `p` among my siblings.</p>
  <div>I am `div` #2.</div>
  <div>I am `div` #3.
    <i>I am the only `i` child.</i>
    <em>I am `em` #1.</em>
    <em>I am `em` #2.</em>
  </div>
</main>

CSS

main :only-of-type {
  color: red;
}

Result

Specifications

Specification Status Comment
Selectors Level 4
The definition of ':only-of-type' in that specification.
Working Draft Matching elements are not required to have a parent.
Selectors Level 3
The definition of ':only-of-type' in that specification.
Recommendation Initial definition.

Browser compatibility

Feature Chrome Edge Firefox (Gecko) Internet Explorer Opera Safari
Basic support 1.0 (Yes) 3.5 (1.9.1) 9.0 9.5 3.2
Feature Android Edge Firefox Mobile (Gecko) IE Mobile Opera Mobile Safari Mobile
Basic support 2.1 (Yes) 1.0 (1.9.1) 9.0 10.0 3.2

See also

Document Tags and Contributors

 Last updated by: chrisdavidmills,