CSS animation property

The animation property is used to animate (gradually change from one style to another) CSS properties with discrete values: layout properties (border, height, width, etc.), properties defining position (left, top), font sizes, colors and opacities.

The animation property is one of the CSS3 properties.

For understanding the animation properties a -webkit- prefix can be needed for older browsers.

Properties, which use a keyword as a value such as display: none; visibility: hidden; or height: auto; cannot be animated.

The @keyframes at-rule

To use animation you must first specify what should happen at specific moments during the animation. This is defined with the @keyframes at-rule.

The @keyframes rule consists of a keyword “@keyframes” followed by animation-name, which identifies the animation. The animation is then applied to an element by using this identifier as a value for the animation-name property.

In curly braces, we put keyframe selectors, which define keyframes (or waypoints) in the animation sequence when the styles should be changed. The keyframe selector can start with a percentage (%) or with the keywords “from” (same as 0%) and “to” (same as 100%). 0% is a starting point of the animation, 100% is the endpoint.

Example of animation with the @keyframe rule:

<!DOCTYPE html>
<html>
  <head>
    <style>
      .element {
        padding: 50px;
        animation: pulse 4s infinite;
      }
      @keyframes pulse {
        0% {
          background-color: #8ebf42;
        }
        50% {
          background-color: #1c87c9;
        }
        100% {
          background-color: #d5dce8;
        }
      }
    </style>
  </head>
  <body>
    <div class="element">Background of this text is animated using CSS3 animation property.</div>
  </body>
</html>

In this example, we bind the animation to the <div> element. The animation will last for 4 seconds, and it will gradually change the background color of the <div> element from "green" to "grey".

Animation is the shorthand property used for setting all the animation properties in a single declaration. We are listing all standard animation-related properties below.

Now let’s see animation-related properties in action.

@keyframes pulse {
  /* declare animation actions here */
}

.element {
  animation-name: pulse;
  animation-duration: 3.5s;
  animation-timing-function: ease-in;
  animation-delay: 1s;
  animation-direction: alternate;
  animation-iteration-count: infinite;
  animation-fill-mode: none;
  animation-play-state: running;
}

/*
  The same can be declared using the animation shorthand property 
*/

.element {
  animation: pulse 3.5s ease-in 1s alternate infinite none running;
}

Animation-name

This property defines the name of the @keyframes rule you want to apply.

animation-name: keyframe-name | none | initial | inherit

Example of the animation-name property:

<!DOCTYPE html>
<html>
  <head>
    <style>
      div {
        padding: 50px;
        animation: element 4s infinite;
      }
      @keyframes element {
        0% {
          background-color: #8ebf42;
        }
        50% {
          background-color: #1c87c9;
        }
        100% {
          background-color: #d5dce8;
        }
      }
    </style>
  </head>
  <body>
    <h2>Animation-name example</h2>
    <div>The name of the animation is set as "element".</div>
  </body>
</html>

Animation-duration

It defines the length of time (in seconds or milliseconds) that animation takes to complete one cycle. If this property is not specified, the animation will not occur.

animation-duration: time | initial | inherit

Example of the animation-duration property:

<!DOCTYPE html>
<html>
  <head>
    <style>
      .element {
        padding: 50px;
        animation: pulse 7s infinite;
      }
      @keyframes pulse {
        0% {
          background-color: #8ebf42;
        }
        50% {
          background-color: #1c87c9;
        }
        100% {
          background-color: #eee
        }
      }
    </style>
  </head>
  <body>
    <div class="element">Background of this text is animated using CSS3 animation property</div>
  </body>
</html>

Animation-timing-function

This property defines how an animation will progress over the duration of each cycle — not throughout the whole of the animation.

animation-timing-function: linear | ease | ease-in | ease-out | ease-in-out | cubic-bezier(n,n,n,n) | initial | inherit

Example of the animation-timing-function property with the “ease” value:

<!DOCTYPE html>
<html>
  <head>
    <title>The title of the document</title>
    <style>
      div {
        width: 100px;
        height: 100px;
        border-radius: 50%;
        background: #1c87c9;
        position: relative;
        -webkit-animation: element 5s infinite;
        /* Safari 4.0 - 8.0 */
        -webkit-animation-timing-function: ease;
        /* Safari 4.0 - 8.0 */
        animation: element 5s infinite;
        animation-timing-function: ease;
      }
      /* Safari 4.0 - 8.0 */
      @-webkit-keyframes element {
        from {
          left: 0px;
        }
        to {
          left: 200px;
        }
      }
      @keyframes element {
        from {
          left: 0px;
        }
        to {
          left: 200px;
        }
      }
    </style>
  </head>
  <body>
    <h2>Animation-timing-function example</h2>
    <div></div>
  </body>
</html>

Animation-delay

This property sets the time (in seconds or milliseconds) between the element being loaded and the start of the animation.

animation-delay: time | initial | inherit

Example of the animation-delay property:

<!DOCTYPE html>
<html>
  <head>
    <style>
      div {
        width: 120px;
        height: 120px;
        background: #1c87c9;
        position: relative;
        animation: delay 5s infinite;
        animation-delay: 3s;
      }
      @keyframes delay {
        from {
          left: 0px;
        }
        to {
          left: 300px;
        }
      }
    </style>
  </head>
  <body>
    <h2>Animation-delay example</h2>
    <p>Here the animation starts after 3 seconds.</p>
    <div></div>
  </body>
</html>

Animation-direction

It defines whether the animation should play in reverse on alternate cycles or not. Its default resets on each cycle.

animation-direction: normal | reverse | alternate | alternate-reverse | initial | inherit

The following values can be applied:

  • normal — (default) - animation is played forward (keyframes 0% - 100%)
  • reverse — animation is played backwards (keyframes (100% - 0%)
  • alternate — the animation is played forward, then it is reversed and repeated.
  • alternate-reverse — the animation is played backwards then forward.

Example of the animation-direction property:

<!DOCTYPE html>
<html>
  <head>
    <style>
      div {
        width: 120px;
        height: 120px;
        background: #ccc;
        position: relative;
        animation: myfirst 5s 1;
        animation-direction: normal;
      }
      @keyframes myfirst {
        0% {
          background: #8DC3CF;
          left: 0px;
          top: 0px;
        }
        25% {
          background: #1c87c9;
          left: 200px;
          top: 0px;
        }
        50% {
          background: #030E10;
          left: 200px;
          top: 200px;
        }
        75% {
          background: #666;
          left: 0px;
          top: 200px;
        }
        100% {
          background: #8ebf42;
          left: 0px;
          top: 0px;
        }
      }
    </style>
  </head>
  <body>
    <h2>Animation-direction example</h2>
    <p>Here the animation plays backwards.</p>
    <div></div>
  </body>
</html>

Animation-iteration-count

Sets the number of times an animation cycle should be played before stopping. The default value is one, but any positive integer value can be set. If you set infinite keyword, the animation will be played endlessly.

A zero or negative integer will never play the animation.
animation-iteration-count: number | infinite | initial | inherit

Example of the animation-iteration-count property:

<!DOCTYPE html>
<html>
  <head>
    <title>Title of the document</title>
    <style>
      html,
      body {
        margin: 0;
        padding: 0;
      }
      div {
        position: relative;
        width: 100px;
        height: 100px;
        margin: 30px 0;
        border-radius: 50%;
        animation-name: pulse;
      }
      .element-one {
        background-color: #1c87c9;
        animation-duration: 3s;
        animation-iteration-count: 3;
      }
      .element-two {
        margin: 0;
        background-color: #83bf42;
        animation-duration: 5s;
        animation-iteration-count: 2;
      }
      @keyframes pulse {
        0% {
          left: 0;
        }
        50% {
          left: 50%;
        }
        100% {
          left: 0;
        }
      }
    </style>
  </head>
  <body>
    <h2>The animation-iteration-count example</h2>
    <p>The animation-iteration-count sets the number of times an animation cycle should be played before stopping.</p>
    <div class="element-one"></div>
    <div class="element-two"></div>
  </body>
</html>

Animation-fill-mode

This property specifies a style for the element applied before or after the animation is executed.

animation-fill-mode: none | forwards | backwards | both | initial | inherit

It can assume the following values:

  • forwards - specifies that the element should keep the style values set by the last keyframe (depends on animation-iteration-count and animation-direction properties).
  • backwards - specifies that the element should get the style values set by the first keyframe (depends on animation-direction) and keep it within animation-delay period.
  • both - specifies that the animation should follow the rules for both forwards and backwards.
  • none - (default) specifies that no style will be applied to the element before or after the animation is executed

Example of the animation-fill-mode property with the “forwards” value:

<!DOCTYPE html>
<html>
  <head>
    <style>
      div {
        width: 100px;
        height: 100px;
        background: #1c87c9;
        position: relative;
        -webkit-animation: element 5s;
        /* Safari 4.0 - 8.0 */
        -webkit-animation-fill-mode: forwards;
        /* Safari 4.0 - 8.0 */
        animation: element 5s;
        animation-fill-mode: forwards;
      }
      /* Safari 4.0 - 8.0 */
      @-webkit-keyframes element {
        from {
          top: 0px;
        }
        to {
          top: 200px;
          background-color: blue;
        }
      }
      @keyframes element {
        from {
          top: 0px;
        }
        to {
          top: 200px;
          background-color: #8ebf42;
        }
      }
    </style>
  </head>
  <body>
    <h2>Animation-fill-mode example</h2>
    <div></div>
  </body>
</html>

Animation-play-state

This property specifies whether the animation is playing or paused.

animation-play-state: paused | running | initial | inherit

The default value is running.

Example of the animation-play-state property with the “running” value:

<!DOCTYPE html>
<html>
  <head>
    <style>
      div {
        width: 150px;
        height: 150px;
        background: #ccc;
        position: relative;
        animation: play 10s;
        animation-play-state: running;
      }
      @keyframes play {
        from {
          left: 0px;
        }
        to {
          left: 200px;
        }
      }
    </style>
  </head>
  <body>
    <h2>Animation-play-state example</h2>
    <p>Here the animation-play-state is set to "running".</p>
    <div></div>
  </body>
</html>

Multiple Animations

It is possible to declare multiple animations on a selector, you just need to separate the values with commas.

Example of multiple animations on a selector:

<!DOCTYPE html>
<html>
  <head>
    <style>
      html,
      body {
        height: 100%;
        margin: 0;
      }
      body {
        display: flex;
        align-items: center;
        justify-content: center;
      }
      .element {
        height: 200px;
        width: 200px;
        background-color: #1c87c9;
        animation: pulse 5s ease infinite alternate, nudge 5s linear infinite alternate;
      }
      @keyframes pulse {
        0%,
        100% {
          background-color: #8ebf42;
        }
        50% {
          background-color: #1c87c9;
        }
      }
      @keyframes nudge {
        0%,
        100% {
          transform: translate(0, 0);
        }
        50% {
          transform: translate(150px, 0);
        }
        80% {
          transform: translate(-150px, 0);
        }
      }
    </style>
  </head>
  <body>
    <div class="element"></div>
  </body>
</html>

Browser support

chrome firefox safari opera
43.0+
4.0-42.0 -webkit-
16.0+
5.0-15.0 -moz-
9.0+
5.1-8.0 -webkit-
12.0+
15.0-29.0 -webkit-

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