Window: scrollTo() method

Syntax

scrollTo(xCoord, yCoord)
scrollTo(options)

Parameters

xCoord

The x-coordinate of the document that you want the viewport's left edge to scroll to.

yCoord

The y-coordinate of the document that you want the viewport's top edge to scroll to.

options

An object containing the following properties:

top Optional

The y-coordinate of the document that you want the viewport's top edge to scroll to. This is the same as the yCoord parameter.

left Optional

The x-coordinate of the document that you want the viewport's left edge to scroll to. This is the same as the xCoord parameter.

behavior Optional

Determines whether scrolling is instant or animates smoothly. This option is a string that must take one of the following values:

• smooth: The scrolling animates smoothly.
• instant: The scrolling happens instantly in a single jump.
• auto: The scroll behavior is determined by the computed value of the scroll-behavior CSS property on the element.

If omitted, behavior defaults to auto.

Return value

A Promise that fulfills with an object containing the following property:

interrupted

A boolean value indicating whether the scrolling operation was interrupted (true) or not (false). Such an interruption typically happens when a programmatic scroll is ongoing, and another programmatic scroll is initiated on the window before the first one finishes.

Examples

Basic usage

window.scrollTo(0, 1000);

Using options:

window.scrollTo({
  top: 100,
  left: 100,
  behavior: "smooth",
});

Responding to the end of the scroll

Our window methods demo (see source code) demonstrates how the promise return value of scrollTo() can be used to respond to the end of a scrolling operation. This technique is mostly useful in cases where the scrolling occurs smoothly over time (achieved by setting the behavior option to smooth, or by setting the scrolling element's scroll-behavior property to smooth).

HTML

Our HTML includes several paragraphs of content and a <div> element toolbar containing <button> elements that trigger various scrolling operations on the window.

<div>
  <button class="scroll">scroll() to 1000</button>
  <button class="scrollto">scrollTo() top</button>
  <button class="scrollby">scrollBy() 200</button>
</div>

<p>...</p>

<p>...</p>

...

CSS

We give the :root element a scroll-behavior property value of smooth so that any scroll operations are animated smoothly over time rather than instantly.

:root {
  scroll-behavior: smooth;
}

We also create two class selectors; when a fade-out or fade-in class is applied to an element, an animation is applied so that it smoothly fades out or in, respectively. We also define @keyframes blocks to define the required opacity changes for those animations.

.fade-out {
  animation: fade-out 0.3s linear both;
}

.fade-in {
  animation: fade-in 0.3s linear both;
}

@keyframes fade-out {
  from {
    opacity: 1;
  }

  to {
    opacity: 0;
  }
}

@keyframes fade-in {
  from {
    opacity: 0;
  }

  to {
    opacity: 1;
  }
}

The rest of the CSS is not shown, for brevity.

JavaScript

We start by grabbing references to the <button> that runs the scrollTo() operation and the toolbar <div>:

const scrollToBtn = document.querySelector(".scrollto");
const toolbar = document.querySelector("div");

Next, we define a function called isInterrupted(), designed to run in response to a scroll operation finishing, which takes a boolean interrupted value as a parameter. It logs a message to the console to say that scrolling is finished and indicate whether the operation was interrupted (interrupted is true) or not. In addition, if interrupted is true, it calls an alert() to clearly indicate the interruption.

function isInterrupted(interrupted) {
  console.log(`Scroll finished;${interrupted ? " " : " not "}interrupted`);
  if (interrupted) {
    alert("Scroll interrupted!");
  }
}

When the button is clicked, we immediately apply the fade-out class to the toolbar, causing it to fade out. We then run scrollTo(0, 0) on the window to scroll its content up to the top, awaiting its promise resolution as we do so and storing the result in a constant. When the promise has resolved, we call isInterrupted() to report that the scroll operation has finished and whether it was interrupted. Finally, we apply the fade-in class to the toolbar, causing it to fade back in again.

scrollToBtn.addEventListener("click", async () => {
  toolbar.className = "fade-out";
  const result = await window.scrollTo(0, 0);
  isInterrupted(result.interrupted);
  toolbar.className = "fade-in";
});

The code not relevant to scrollTo() is not shown, for brevity.

Result

Click the buttons to see the scrolling behavior. Note how the toolbar fades out when a button is pressed, and fades in again once the smooth scrolling is finished. Also try pressing one button and then quickly pressing another button before the first scrolling operation has finished. Note how, in these cases, the scrolling is reported as interrupted.

You can also load the demo in a separate tab and view the source code.

Aside on feature detection

If you run this example in a browser that doesn't support promise-returning scroll operations, the scroll operations are still smooth, but the toolbar doesn't fade out and then fade back in once the operation is finished. The feature detection is handled by a function called supportsScrollPromises(), which runs a scroll operation and tests whether its return value is a promise:

function supportsScrollPromises() {
  const test = window.scroll(0, 0);
  return test instanceof Promise;
}

Check out the source code to see how the feature detection is used.

Specifications

Browser compatibility

See also

• Window.scroll()
• Window.scrollBy()
• Element.scrollTo()
• Window.scrollByLines()
• Window.scrollByPages()