PerformanceElementTiming.intersectionRect

Experimental: This is an experimental technology
Check the Browser compatibility table carefully before using this in production.

The intersectionRect read-only property of the PerformanceElementTiming interface returns the rectangle of the element within the viewport.

Value

A DOMRectReadOnly which is the rectangle of the element within the viewport.

For display images this is the display rectangle of the image within the viewport. For text this is the display rectangle of the node in the viewport. This being the smallest rectangle that contains the union of all text nodes that belong to the element.

Examples

Logging intersectionRect

In this example an <img> element is being observed by adding the elementtiming attribute. A PerformanceObserver is registered to get all performance entries of type "element" and the buffered flag is used to access data from before observer creation. Calling entry.intersectionRect returns a DOMRectReadOnly object with the display rectangle of the image.

<img
  src="image.jpg"
  alt="a nice image"
  elementtiming="big-image"
  id="myImage" />
const observer = new PerformanceObserver((list) => {
  list.getEntries().forEach((entry) => {
    if (entry.identifier === "big-image") {
      console.log(entry.intersectionRect);
    }
  });
});
observer.observe({ type: "element", buffered: true });

Specifications

Specification
Element Timing API
# ref-for-dom-performanceelementtiming-intersectionrect

Browser compatibility

BCD tables only load in the browser