opacity

Avatar of Sara Cope
Sara Cope on (Updated on )

UGURUS offers elite coaching and mentorship for agency owners looking to grow. Start with the free Agency Accelerator today.

The opacity property in CSS specifies how transparent an element is.

Basic use:

div {
  opacity: 0.5;
}

Opacity has a default initial value of 1 (100% opaque). Opacity is not inherited, but because the parent has opacity that applies to everything within it. You cannot make a child element less transparent than the parent, without some trickery. Values are a number from 0 to 1 representing the opacity of the channel (the “alpha” channel). When an element has a value of 0 the element is completely invisible; a value of 1 is completely opaque (solid).

Check out this Pen!

IE Compatibility

If you want opacity to work in all versions of IE, the order should be as follows:

.opaque {
  /* Theoretically for IE 8 & 9 (more valid) */
  /* ...but not required as filter works too */
  /* should come BEFORE filter */
  -ms-filter:"progid:DXImageTransform.Microsoft.Alpha(Opacity=50)"; // IE8

  /* This works in IE 8 & 9 too */
  /* ... but also 5, 6, 7 */
  filter: alpha(opacity=50); // IE 5-7
  
  /* Modern Browsers */
  opacity: 0.5;
}

If you don’t use this order, IE8-as-IE7 doesn’t apply the opacity, although IE8 and a pure IE7 do.

Note on Stacking Contexts

If an element with opacity and a value less than 1 is positioned, the z-index property applies as described in CSS2.1, except that the auto value is treated as 0 since a new stacking context is always created.

Opacity can be used as an alternative to the visibility property: visibility: hidden; is just like opacity: 0;.

Related Properties

Other Resources

Browser Support

Chrome Safari Firefox Opera IE Android iOS
24+ 5.1+ 19+ 12.1+ 9+ 2.1+ 3.2+