acos()
Baseline 2023
Newly available
Since March 2023, this feature works across the latest devices and browser versions. This feature might not work in older devices or browsers.
The acos()
CSS function is a trigonometric function that returns the inverse cosine of a number between -1
and 1
. The function contains a single calculation that returns the number of radians representing an <angle>
between 0deg
and 180deg
.
Syntax
css
/* Single <number> values */
transform: rotate(acos(-0.2));
transform: rotate(acos(2 * 0.125));
/* Other values */
transform: rotate(acos(pi / 5));
transform: rotate(acos(e / 3));
Parameters
Return value
The inverse cosine of an number
will always return an <angle>
between 0deg
and 180deg
.
- If
number
is less than-1
or greater than1
, the result isNaN
. - If
number
is exactly1
, the result is0
.
Formal syntax
Examples
Rotate elements
The acos()
function can be used to rotate
elements as it return an <angle>
.
HTML
html
<div class="box box-1"></div>
<div class="box box-2"></div>
<div class="box box-3"></div>
<div class="box box-4"></div>
<div class="box box-5"></div>
CSS
css
div.box {
width: 100px;
height: 100px;
background: linear-gradient(orange, red);
}
div.box-1 {
transform: rotate(acos(1));
}
div.box-2 {
transform: rotate(acos(0.5));
}
div.box-3 {
transform: rotate(acos(0));
}
div.box-4 {
transform: rotate(acos(-0.5));
}
div.box-5 {
transform: rotate(acos(-1));
}
Result
Specifications
Specification |
---|
CSS Values and Units Module Level 4 # trig-funcs |
Browser compatibility
BCD tables only load in the browser