`opacity()` CSS function

Baseline Widely available

This feature is well established and works across many devices and browser versions. It's been available across browsers since September 2016.

The opacity() CSS function applies transparency to the samples in the input image. Its result is a <filter-function>.

Try it

filter: opacity(1);

filter: opacity(80%);

filter: opacity(50%);

filter: opacity(0.2);

filter: opacity(0);

<section id="default-example">
  <img
    class="transition-all"
    id="example-element"
    src="/shared-assets/images/examples/firefox-logo.svg"
    width="200" />
</section>

Note: This function is similar to the more established opacity property. The difference is that with filters, some browsers provide hardware acceleration for better performance.

Syntax

opacity(amount)

Parameters

amount Optional: The amount of the conversion, specified as a <number> or a <percentage>. A value of 0% is completely transparent, while a value of 100% leaves the input unchanged. Values between 0% and 100% are linear multipliers on the effect. The initial value for interpolation is 1. The default value is 1.

Formal syntax

<opacity()> = 
  opacity( [ <number> | <percentage> ]? )

Examples

Examples of correct values for opacity()

opacity(0%)   /* Completely transparent */
opacity(50%)  /* 50% transparent */

opacity()     /* No effect */
opacity(1)

Specifications

Specification
Filter Effects Module Level 1 # funcdef-filter-opacity

Browser compatibility

	Desktop					Mobile
	Chrome	Edge	Firefox	Opera	Safari	Chrome Android	Firefox for Android	Opera Android	Safari on iOS	Samsung Internet	WebView Android	WebView on iOS
`opacity`	18	12	35	15	6	53	35	14	6	6.0	4.4	6