Support CoreUI Development

CoreUI is an MIT-licensed open source project and is completely free to use. However, the amount of effort needed to maintain and develop new features for the project is not sustainable without proper financial backing.

You can support our Open Source software development in the following ways:

  • Buy the CoreUI PRO, and get access to PRO components, and dedicated support.
  • Became a sponsor, and get your logo on files or each site of this documentation
  • Give us a star ⭐️ on Github.


Control the opacity of elements.

The opacity property sets the opacity level for an element. The opacity level describes the transparency level, where 1 is not transparent at all, .5 is 50% visible, and 0 is completely transparent.

Set the opacity of an element using .opacity-{value} utilities.

<div class="opacity-100">...</div>
<div class="opacity-75">...</div>
<div class="opacity-50">...</div>
<div class="opacity-25">...</div>

Utilities API

Opacity utilities are declared in our utilities API in scss/_utilities.scss. Learn how to use the utilities API.

    "opacity": (
      property: opacity,
      values: (
        0: 0,
        25: .25,
        50: .5,
        75: .75,
        100: 1,