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css function

`asin()` CSS function

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The asin() CSS function is a trigonometric function that returns the inverse sine of a number between -1 and 1. The function contains a single calculation that returns an angle between -90deg and 90deg.

Syntax

/* Single <number> values */
transform: rotate(asin(-0.2));
transform: rotate(asin(2 * 0.125));

/* Other values */
transform: rotate(asin(pi / 5));
transform: rotate(asin(e / 3));

Parameters

The asin(number) function accepts only one value as its parameter.

  • number
    • : A calculation which resolves to a &lt;number&gt; between -1 and 1.

Return value

The inverse sine of a number will always return an angle between -90deg and 90deg.

  • If number is less than -1 or greater than 1, the result is NaN.
  • If number is 0⁻, the result is 0⁻.

Formal syntax

Examples

Rotate elements

The asin() function can be used to rotate elements as it return an angle.

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

body {
  height: 100vh;
  display: flex;
  justify-content: center;
  align-items: center;
  gap: 50px;
}

div.box {
  width: 100px;
  height: 100px;
  background: linear-gradient(orange, red);
}
div.box-1 {
  transform: rotate(asin(1));
}
div.box-2 {
  transform: rotate(asin(0.5));
}
div.box-3 {
  transform: rotate(asin(0));
}
div.box-4 {
  transform: rotate(asin(-0.5));
}
div.box-5 {
  transform: rotate(asin(-1));
}

Result

Interactive exampleOpen the canonical MDN source to run this embedded demo.

Specifications

SpecificationsStandards references are available on the canonical MDN page.

Browser compatibility

Browser compatibilityCompatibility data is available on the canonical MDN page.

See also