Skeleton

<sl-skeleton> | SlSkeleton
Since 2.0 stable

Skeletons are used to provide a visual representation of where content will eventually be drawn.

These are simple containers for scaffolding layouts that mimic what users will see when content has finished loading. This prevents large areas of empty space during asynchronous operations.

Skeletons try not to be opinionated, as there are endless possibilities for designing layouts. Therefore, you’ll likely use more than one skeleton to create the effect you want. If you find yourself using them frequently, consider creating a template that renders them with the desired arrangement and styles. 

<div class="skeleton-overview">
  <header>
    <sl-skeleton></sl-skeleton>
    <sl-skeleton></sl-skeleton>
  </header>

  <sl-skeleton></sl-skeleton>
  <sl-skeleton></sl-skeleton>
  <sl-skeleton></sl-skeleton>
</div>

<style>
  .skeleton-overview header {
    display: flex;
    align-items: center;
    margin-bottom: 1rem;
  }

  .skeleton-overview header sl-skeleton:last-child {
    flex: 0 0 auto;
    width: 30%;
  }

  .skeleton-overview sl-skeleton {
    margin-bottom: 1rem;
  }

  .skeleton-overview sl-skeleton:nth-child(1) {
    float: left;
    width: 3rem;
    height: 3rem;
    margin-right: 1rem;
    vertical-align: middle;
  }

  .skeleton-overview sl-skeleton:nth-child(3) {
    width: 95%;
  }

  .skeleton-overview sl-skeleton:nth-child(4) {
    width: 80%;
  }
</style>

Examples

Effects

There are two built-in effects, sheen and pulse. Effects are intentionally subtle, as they can be distracting when used extensively. The default is none, which displays a static, non-animated skeleton.

None Sheen Pulse 
<div class="skeleton-effects">
  <sl-skeleton effect="none"></sl-skeleton>
  None

  <sl-skeleton effect="sheen"></sl-skeleton>
  Sheen

  <sl-skeleton effect="pulse"></sl-skeleton>
  Pulse
</div>

<style>
  .skeleton-effects {
    font-size: var(--sl-font-size-small);
  }

  .skeleton-effects sl-skeleton:not(:first-child) {
    margin-top: 1rem;
  }
</style>

Paragraphs

Use multiple skeletons and some clever styles to simulate paragraphs.

<div class="skeleton-paragraphs">
  <sl-skeleton></sl-skeleton>
  <sl-skeleton></sl-skeleton>
  <sl-skeleton></sl-skeleton>
  <sl-skeleton></sl-skeleton>
  <sl-skeleton></sl-skeleton>
</div>

<style>
  .skeleton-paragraphs sl-skeleton {
    margin-bottom: 1rem;
  }

  .skeleton-paragraphs sl-skeleton:nth-child(2) {
    width: 95%;
  }

  .skeleton-paragraphs sl-skeleton:nth-child(4) {
    width: 90%;
  }

  .skeleton-paragraphs sl-skeleton:last-child {
    width: 50%;
  }
</style>

Avatars

Set a matching width and height to make a circle, square, or rounded avatar skeleton.

<div class="skeleton-avatars">
  <sl-skeleton></sl-skeleton>
  <sl-skeleton></sl-skeleton>
  <sl-skeleton></sl-skeleton>
</div>

<style>
  .skeleton-avatars sl-skeleton {
    display: inline-block;
    width: 3rem;
    height: 3rem;
    margin-right: 0.5rem;
  }

  .skeleton-avatars sl-skeleton:nth-child(1) {
    --border-radius: 0;
  }

  .skeleton-avatars sl-skeleton:nth-child(2) {
    --border-radius: var(--sl-border-radius-medium);
  }
</style>

Custom Shapes

Use the --border-radius custom property to make circles, squares, and rectangles. For more complex shapes, you can apply clip-path to the indicator part. Try Clippy if you need help generating custom shapes. 

<div class="skeleton-shapes">
  <sl-skeleton class="square"></sl-skeleton>
  <sl-skeleton class="circle"></sl-skeleton>
  <sl-skeleton class="triangle"></sl-skeleton>
  <sl-skeleton class="cross"></sl-skeleton>
  <sl-skeleton class="comment"></sl-skeleton>
</div>

<style>
  .skeleton-shapes sl-skeleton {
    display: inline-flex;
    width: 50px;
    height: 50px;
  }

  .skeleton-shapes .square::part(indicator) {
    --border-radius: var(--sl-border-radius-medium);
  }

  .skeleton-shapes .circle::part(indicator) {
    --border-radius: var(--sl-border-radius-circle);
  }

  .skeleton-shapes .triangle::part(indicator) {
    --border-radius: 0;
    clip-path: polygon(50% 0, 0 100%, 100% 100%);
  }

  .skeleton-shapes .cross::part(indicator) {
    --border-radius: 0;
    clip-path: polygon(
      20% 0%,
      0% 20%,
      30% 50%,
      0% 80%,
      20% 100%,
      50% 70%,
      80% 100%,
      100% 80%,
      70% 50%,
      100% 20%,
      80% 0%,
      50% 30%
    );
  }

  .skeleton-shapes .comment::part(indicator) {
    --border-radius: 0;
    clip-path: polygon(0% 0%, 100% 0%, 100% 75%, 75% 75%, 75% 100%, 50% 75%, 0% 75%);
  }

  .skeleton-shapes sl-skeleton:not(:last-child) {
    margin-right: 0.5rem;
  }
</style>

Custom Colors

Set the --color and --sheen-color custom properties to adjust the skeleton’s color. 

<sl-skeleton effect="sheen" style="--color: tomato; --sheen-color: #ffb094;"></sl-skeleton>

Properties

Name Description Reflects Type Default
effect Determines which effect the skeleton will use. 'pulse' | 'sheen' | 'none' 'none'
updateComplete A read-only promise that resolves when the component has finished updating.

Learn more about attributes and properties.

Custom Properties

Name Description Default
--border-radius The skeleton’s border radius.
--color The color of the skeleton.
--sheen-color The sheen color when the skeleton is in its loading state.

Learn more about customizing CSS custom properties.

Parts

Name Description
base The component’s base wrapper.
indicator The skeleton’s indicator which is responsible for its color and animation.

Learn more about customizing CSS parts.