`text-decoration-thickness` CSS property

The text-decoration-thickness CSS property sets the stroke thickness of the decoration line that is used on text in an element, such as a line-through, underline, or overline.

Try it

text-decoration-line: underline;
text-decoration-thickness: 3px;

text-decoration-line: line-through;
text-decoration-thickness: 0.4rem;

text-decoration-line: underline overline;
text-decoration-thickness: from-font;
font-size: 2rem;

<section id="default-example">
  <p id="example-element">
    Confusion kissed me on the cheek, and left a taste so bittersweet
  </p>
</section>

p {
  font: 1.5em sans-serif;
  text-decoration-color: red;
}

Syntax

/* Single keyword */
text-decoration-thickness: auto;
text-decoration-thickness: from-font;

/* length */
text-decoration-thickness: 0.1em;
text-decoration-thickness: 3px;

/* percentage */
text-decoration-thickness: 10%;

/* Global values */
text-decoration-thickness: inherit;
text-decoration-thickness: initial;
text-decoration-thickness: revert;
text-decoration-thickness: revert-layer;
text-decoration-thickness: unset;

Values

auto

The browser chooses an appropriate width for the text decoration line.

from-font

If the font file includes information about a preferred thickness, use that value. If the font file doesn't include this information, behave as if auto was set, with the browser choosing an appropriate thickness.

<length>

Specifies the thickness of the text decoration line as a <length>, overriding the font file suggestion or the browser default.

<percentage>

Specifies the thickness of the text decoration line as a <percentage> of 1em in the current font. A percentage inherits as a relative value, and so therefore scales with changes in the font. The browser must use a minimum of 1 device pixel. For a given application of this property, the thickness is constant across the whole box it is applied to, even if there are child elements with a different font size.

Formal definition

Formal syntax

text-decoration-thickness = 
  auto |
  from-font |
  <length> |
  <percentage>

Examples

Varying thickness

HTML

<p class="thin">Here's some text with a 1px red underline.</p>
<p class="thick">This one has a 5px red underline.</p>
<p class="shorthand">This uses the equivalent shorthand.</p>

CSS

.thin {
  text-decoration-line: underline;
  text-decoration-style: solid;
  text-decoration-color: red;
  text-decoration-thickness: 1px;
}

.thick {
  text-decoration-line: underline;
  text-decoration-style: solid;
  text-decoration-color: red;
  text-decoration-thickness: 5px;
}

.shorthand {
  text-decoration: underline solid red 5px;
}

Results

Specifications

Browser compatibility

See also

• text-decoration
• text-underline-offset