The text-underline-position
CSS property specifies the position of the underline which is set using the text-decoration
property's underline
value.
The source for this interactive example is stored in a GitHub repository. If you'd like to contribute to the interactive examples project, please clone https://github.com/mdn/interactive-examples and send us a pull request.
Syntax
/* Single keyword */ text-underline-position: auto; text-underline-position: under; text-underline-position: left; text-underline-position: right; /* Multiple keywords */ text-underline-position: under left; text-underline-position: right under; /* Global values */ text-underline-position: inherit; text-underline-position: initial; text-underline-position: unset;
Syntax
Values
auto
- The user agent uses its own algorithm to place the line at or under the alphabetic baseline.
from-font
- If the font file includes information about a preferred position, use that value. If the font file doesn't include this information, behave as if
auto
was set, with the browser choosing an appropriate position. under
- Forces the line to be set below the alphabetic baseline, at a position where it won't cross any descenders. This is useful for ensuring legibility with chemical and mathematical formulas, which make a large use of subscripts.
left
- In vertical writing-modes, this keyword forces the line to be placed on the left side of the text. In horizontal writing-modes, it is a synonym of
under
. right
- In vertical writing-modes, this keyword forces the line to be placed on the right side of the text. In horizontal writing-modes, it is a synonym of
under
. auto-pos
- A synonym of
auto
, which should be used instead. above
- Forces the line to be above the text. When used with East-Asian text, using the
auto
keyword will lead to a similar effect. below
- Forces the line to be below the text. When used with alphabetic text, using the
auto
keyword will lead to a similar effect.
Formal definition
Initial value | auto |
---|---|
Applies to | all elements |
Inherited | yes |
Computed value | as specified |
Animation type | discrete |
Formal syntax
auto | from-font | [ under | [ left | right ] ]
Examples
A simple example
Let's take a couple of simple example paragraphs:
<p class="horizontal">Lorem ipsum dolor sit amet, consectetur adipiscing elit. Nullam consectetur ac turpis vel laoreet. Nullam volutpat pharetra lorem, sit amet feugiat tortor volutpat quis. Nam eget sodales quam. Aliquam accumsan tellus ac erat posuere.</p> <p class="vertical">Lorem ipsum dolor sit amet, consectetur adipiscing elit. Nullam consectetur ac turpis vel laoreet. Nullam volutpat pharetra lorem, sit amet feugiat tortor volutpat quis. Nam eget sodales quam. Aliquam accumsan tellus ac erat posuere.</p>
Our CSS looks like this:
p { font-size: 1.5rem; text-transform: capitalize; text-decoration: underline; text-decoration-thickness: 2px; } .horizontal { text-underline-position: under; } .vertical { writing-mode: vertical-rl; text-underline-position: left; }
In this example we set both the paragraphs to have a thick underline. In the horizontal text we use text-underline-position: under;
to put the underline below all the descenders.
In the text with a vertical writing-mode
set, we can then use values of left
or right
to make the underline appear on the left or right of the text as required.
The live example looks like this:
Setting text-underline-position globally
Because the text-underline-position
property inherits and is not reset by the text-decoration
shorthand property, it may be appropriate to set its value at a global level. For example, the under
value may be appropriate for a document with lots of chemical and mathematical formulas, which make a large use of subscripts.
:root { text-underline-position: under; }
Specifications
Specification | Status | Comment |
---|---|---|
CSS Text Decoration Module Level 3 The definition of 'text-underline-position' in that specification. |
Candidate Recommendation | Initial definition |
Browser compatibility
Desktop | Mobile | |||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|
text-underline-position | Chrome Full support 33 | Edge Full support 12 | Firefox Full support 74 | IE Full support 6 | Opera Full support 20 | Safari
Full support
12.1
| WebView Android Full support 4.4.3 | Chrome Android Full support 33 | Firefox Android No support No | Opera Android Full support 20 | Safari iOS No support No | Samsung Internet Android Full support 2.0 |
above and below | Chrome No support No | Edge No support 12 — 79 | Firefox Full support 74 | IE Full support 6 | Opera No support No | Safari No support No | WebView Android No support No | Chrome Android No support No | Firefox Android No support No | Opera Android No support No | Safari iOS No support No | Samsung Internet Android No support No |
auto-pos | Chrome No support No | Edge No support 12 — 79 | Firefox No support No | IE Full support 6 | Opera No support No | Safari No support No | WebView Android No support No | Chrome Android No support No | Firefox Android No support No | Opera Android No support No | Safari iOS No support No | Samsung Internet Android No support No |
from-font | Chrome No support No | Edge No support No | Firefox Full support 74 | IE No support No | Opera No support No | Safari No support No | WebView Android No support No | Chrome Android No support No | Firefox Android No support No | Opera Android No support No | Safari iOS No support No | Samsung Internet Android No support No |
left and right | Chrome Full support 71 | Edge Full support 79 | Firefox Full support 74 | IE No support No | Opera Full support 58 | Safari No support No | WebView Android Full support 71 | Chrome Android Full support 71 | Firefox Android No support No | Opera Android Full support 50 | Safari iOS No support No | Samsung Internet Android Full support 10.0 |
under | Chrome Full support 33 | Edge Full support 79 | Firefox Full support 74 | IE No support No | Opera Full support 20 | Safari Full support 12.1 | WebView Android Full support 4.4.3 | Chrome Android Full support 33 | Firefox Android No support No | Opera Android Full support 20 | Safari iOS No support No | Samsung Internet Android Full support 2.0 |
Legend
- Full support
- Full support
- No support
- No support
- Experimental. Expect behavior to change in the future.
- Experimental. Expect behavior to change in the future.
- Non-standard. Expect poor cross-browser support.
- Non-standard. Expect poor cross-browser support.
- Requires a vendor prefix or different name for use.
- Requires a vendor prefix or different name for use.
See also
- The
text-decoration
property is a shorthand for setting most text-decoration properties, includingtext-decoration-line
,text-decoration-color
, andtext-decoration-style
. However, it does not settext-underline-position
. - Microsoft non-standard values documentation