Web/CSS/animation-timing-function

The animation-timing-function CSS property sets how an animation progresses through the duration of each cycle.

It is often convenient to use the shorthand property animation to set all animation properties at once.

Syntax

/* Keyword values */
animation-timing-function: ease;
animation-timing-function: ease-in;
animation-timing-function: ease-out;
animation-timing-function: ease-in-out;
animation-timing-function: linear;
animation-timing-function: step-start;
animation-timing-function: step-end;

/* Function values */
animation-timing-function: cubic-bezier(0.1, 0.7, 1.0, 0.1);
animation-timing-function: steps(4, end);

/* Steps Function keywords */ 
animation-timing-function: steps(4, jump-start);
animation-timing-function: steps(10, jump-end);
animation-timing-function: steps(20, jump-none);
animation-timing-function: steps(5, jump-both);
animation-timing-function: steps(6, start);
animation-timing-function: steps(8, end);

/* Multiple animations */
animation-timing-function: ease, step-start, cubic-bezier(0.1, 0.7, 1.0, 0.1);

/* Global values */
animation-timing-function: inherit;
animation-timing-function: initial;
animation-timing-function: unset;

Timing functions may be specified on individual keyframes in a @keyframes rule. If no animation-timing-function is specified on a keyframe, the corresponding value of animation-timing-function from the element to which the animation is applied is used for that keyframe.

A keyframe's timing function is applied on a property-by-property basis from the keyframe on which it is specified until the next keyframe specifying that property, or until the end of the animation if there is no subsequent keyframe specifying that property. As a result, an animation-timing-function specified on the 100% or to keyframe will never be used.

Values

<timing-function>

The timing function that corresponds to a given animation, as determined by animation-name.

The non-step keyword values (ease, linear, ease-in-out, etc.) each represent cubic Bézier curve with fixed four point values, with the cubic-bezier() function value allowing for a non-predefined value. The step timing functions divides the input time into a specified number of intervals that are equal in length. It is defined by a number of steps and a step position.

ease

Equal to cubic-bezier(0.25, 0.1, 0.25, 1.0), the default value, increases in velocity towards the middle of the animation, slowing back down at the end.

linear

Equal to cubic-bezier(0.0, 0.0, 1.0, 1.0), animates at an even speed.

ease-in

Equal to cubic-bezier(0.42, 0, 1.0, 1.0), starts off slowly, with the speed of the transition of the animating properting increasing until complete.

ease-out

Equal to cubic-bezier(0, 0, 0.58, 1.0), starts quickly, slowing down the animation continues. •

ease-in-out

Equal to cubic-bezier(0.42, 0, 0.58, 1.0), with the animating properties slowly transitioning, speeding up, and then slowing down again.

cubic-bezier(p1, p2, p3, p4)

An author defined cubic-bezier curve, where the p1 and p3 values must be in the range of 0 to 1.

steps(n, <jumpterm>)

Displays an animation iteration along n stops along the transition, displaying each stop for equal lengths of time. For example, if n is 5, there are 5 steps. Whether the animation holds temporarily at 0%, 20%, 40%, 60% and 80%, on the 20%, 40%, 60%, 80% and 100%, or makes 5 stops between the 0% and 100% along the animation, or makes 5 stops including the 0% and 100% marks (on the 0%, 25%, 50%, 75%, and 100%) depends on which of the following jump terms is used:

jump-start: Denotes a left-continuous function, so that the first jump happens when the animation begins;
jump-end: Denotes a right-continuous function, so that the last jump happens when the animation ends;
jump-none: There is no jump on either end. Instead, holding at both the 0% mark and the 100% mark, each for 1/n of the duration.
jump-both: Includes pauses at both the 0% and 100% marks, effectively adding a step during the animation iteration.
start: Same as jump-start.
end: Same as jump-end.

step-start

Equal to steps(1, jump-start)

step-end

Equal to steps(1, jump-end)

Note: When you specify multiple comma-separated values on an animation-* property, they will be assigned to the animations specified in the animation-name property in different ways depending on how many there are. For more information, see Setting multiple animation property values.

Formal definition

Initial value	`ease`
Applies to	all elements, `::before` and `::after` pseudo-elements
Inherited	no
Computed value	as specified
Animation type	discrete

Formal syntax

<timing-function>#where <timing-function> = linear | <cubic-bezier-timing-function> | <step-timing-function>where <cubic-bezier-timing-function> = ease | ease-in | ease-out | ease-in-out | cubic-bezier(<number <a href="/en-US/docs/CSS/Value_definition_syntax#Brackets" title="Brackets: enclose several entities, combinators, and multipliers to transform them as a single component">[0,1]>, <number>, <number <a href="/en-US/docs/CSS/Value_definition_syntax#Brackets" title="Brackets: enclose several entities, combinators, and multipliers to transform them as a single component">[0,1]>, <number>)<step-timing-function> = step-start | step-end | steps(<integer>[, <step-position>]?)where <step-position> = jump-start | jump-end | jump-none | jump-both | start | end

Examples

Cubic-Bezier examples

<div class="parent"> 
  <div class="ease">ease</div>
  <div class="easein">ease-in</div>
  <div class="easeout">ease-out</div>
  <div class="easeinout">ease-in-out</div>
  <div class="linear">linear</div>
  <div class="cb">cubic-bezier(0.2,-2,0.8,2)</div>
</div>

.parent > div[class] {
    animation-name: changeme;
    animation-duration: 10s;
    animation-iteration-count: infinite;
    margin-bottom: 4px;
}
@keyframes changeme {
   0% {
      min-width: 12em;
      width: 12em; 
      background-color: black; 
      border: 1px solid red; 
      color: white;
   }
   100% {
      width: 90vw; 
      min-width: 24em; 
      background-color: magenta; 
      color: yellow;
      border: 1px solid orange; 
   }
}

.ease {
   animation-timing-function: ease;
}
.easein {
   animation-timing-function: ease-in;
}
.easeout {
   animation-timing-function: ease-out;
}
.easeinout {
   animation-timing-function: ease-in-out;
}
.linear {
   animation-timing-function: linear;
}
.cb {
   animation-timing-function: cubic-bezier(0.2,-2,0.8,2);
}

Step examples

<div class="parent"> 
  <div class="jump-start">jump-start</div>
  <div class="jump-end">jump-end</div>
  <div class="jump-both">jump-both</div>
  <div class="jump-none">jump-none</div>
  <div class="start">start</div>
  <div class="end">end</div>
  <div class="step-start">step-start</div>
  <div class="step-end">step-end</div>
</div>

.parent > div[class] { 
    animation-name: changeme;
    animation-duration: 10s;
    animation-iteration-count: infinite;
    margin-bottom: 4px;
}
@keyframes changeme {
   0% {
      min-width: 12em; 
      width: 12em;
      background-color: black; 
      border: 1px solid red; 
      color: white;
   }
   100% {
      width: 90vw; 
      min-width: 24em; 
      background-color: magenta; 
      color: yellow;
      border: 1px solid orange; 
   }
}

.jump-start {
   animation-timing-function: steps(5, jump-start);
}
.jump-end {
   animation-timing-function: steps(5, jump-end);
}
.jump-none {
   animation-timing-function: steps(5, jump-none);
}
.jump-both {
   animation-timing-function: steps(5, jump-both);
}
.start { 
   animation-timing-function: steps(5, start); 
} 
.end { 
   animation-timing-function: steps(5, end); 
}
.step-start {
   animation-timing-function: step-start;
}
.step-end {
   animation-timing-function: step-end;
}

Specifications

Specification	Status	Comment
CSS AnimationsThe definition of 'animation-timing-function' in that specification.	Working Draft	Initial definition.

Browser compatibility

Update compatibility data on GitHub

	Desktop						Mobile
	Chrome	Edge	Firefox	Internet Explorer	Opera	Safari	Android webview	Chrome for Android	Firefox for Android	Opera for Android	Safari on iOS	Samsung Internet
`animation-timing-function`	Chrome Full support 43 Full support 43 Full support 3 Prefixed' Prefixed' Implemented with the vendor prefix: -webkit-	Edge Full support 12 Full support 12 Full support 12 Prefixed' Prefixed' Implemented with the vendor prefix: -webkit-	Firefox Full support 16 Full support 16 Full support 49 Prefixed' Prefixed' Implemented with the vendor prefix: -webkit- Full support 44 Prefixed' Disabled' Prefixed' Implemented with the vendor prefix: -webkit- Disabled' From version 44: this feature is behind the `layout.css.prefixes.webkit` preference (needs to be set to `true`). To change preferences in Firefox, visit about:config. Full support 5 Prefixed' Prefixed' Implemented with the vendor prefix: -moz-	IE Full support 10	Opera Full support 30 Full support 30 Full support 15 Prefixed' Prefixed' Implemented with the vendor prefix: -webkit- No support 12.1 — 15 No support 12 — 15 Prefixed' Prefixed' Implemented with the vendor prefix: -o-	Safari Full support 9 Full support 9 Full support 4 Prefixed' Prefixed' Implemented with the vendor prefix: -webkit-	WebView Android Full support 43 Full support 43 Full support ≤37 Prefixed' Prefixed' Implemented with the vendor prefix: -webkit-	Chrome Android Full support 43 Full support 43 Full support 18 Prefixed' Prefixed' Implemented with the vendor prefix: -webkit-	Firefox Android Full support 16 Full support 16 Full support 49 Prefixed' Prefixed' Implemented with the vendor prefix: -webkit- Full support 44 Prefixed' Disabled' Prefixed' Implemented with the vendor prefix: -webkit- Disabled' From version 44: this feature is behind the `layout.css.prefixes.webkit` preference (needs to be set to `true`). To change preferences in Firefox, visit about:config. Full support 5 Prefixed' Prefixed' Implemented with the vendor prefix: -moz-	Opera Android Full support 30 Full support 30 Full support 14 Prefixed' Prefixed' Implemented with the vendor prefix: -webkit- No support 12.1 — 14 No support 12 — 14 Prefixed' Prefixed' Implemented with the vendor prefix: -o-	Safari iOS Full support 9 Full support 9 Full support 3.2 Prefixed' Prefixed' Implemented with the vendor prefix: -webkit-	Samsung Internet Android Full support 4.0 Full support 4.0 Full support 1.0 Prefixed' Prefixed' Implemented with the vendor prefix: -webkit-
`jump-` keywords for `steps()`	Chrome Full support 77	Edge Full support 79	Firefox Full support 65	IE No support No	Opera Full support 64	Safari Full support 14	WebView Android Full support 77	Chrome Android Full support 77	Firefox Android Full support 65	Opera Android Full support 55	Safari iOS Full support 14	Samsung Internet Android Full support 12.0

Legend

Full support: Full support
No support: No support
User must explicitly enable this feature.': User must explicitly enable this feature.
Requires a vendor prefix or different name for use.': Requires a vendor prefix or different name for use.