index.md

---

title: Animation.persist()
slug: Web/API/Animation/persist
page-type: web-api-instance-method
browser-compat: api.Animation.persist

---

{{APIRef("Web Animations")}}

The persist() method of the Web Animations API's {{domxref("Animation")}} interface explicitly persists an animation, when it would otherwise be removed due to the browser's Automatically removing filling animations behavior.

Syntax

persist()

Parameters

None.

Return value

None ({{jsxref("undefined")}}).

Examples

In our simple replace indefinite animations demo, you can see the following code:

const divElem = document.querySelector("div");

document.body.addEventListener("mousemove", (evt) => {
  const anim = divElem.animate(
    { transform: `translate(${evt.clientX}px, ${evt.clientY}px)` },
    { duration: 500, fill: "forwards" }
  );

  anim.commitStyles();

  //anim.persist()

  anim.onremove = (event) => {
    console.log("Animation removed");
  };

  console.log(anim.replaceState);
});

Here we have a <div> element, and an event listener that fires the event handler code whenever the mouse moves. The event handler sets up an animation that animates the <div> element to the position of the mouse pointer. This could result in a huge animations list, which could create a memory leak. For this reason, modern browsers automatically remove overriding forward filling animations.

You can see the replaceState of the animation being logged at the end of the handler. This will be active for each animation by default, or persisted if the persist() call is uncommented.

Specifications

{{Specifications}}

Browser compatibility

{{Compat}}

See also

• Web Animations API

• {{domxref("Animation")}} for other methods and properties you can use to control web page animation.