PDFPageImageLayer: metrics property

Works in all major browsers

Since July 2026

WebPDF works in Chrome and Edge 125, Firefox 153 and Safari 18, on desktop and mobile, and in every later version: the oldest versions its PDF.js build supports, which already have every platform feature WebPDF needs. Since July 2026, that is every major browser.

The metrics read-only property of the PDFPageImageLayer interface returns the size of the image a <pdf-page> has drawn.

Value

An object, or undefined before the page has drawn:

width: The image's width in pixels: the canvas's pixel width, or the SVG's width.
height: The image's height in pixels.
aspectRatio: A string such as "612 / 792", ready for the CSS aspect-ratio property.
orientation: An object with three booleans, of which one is true: portrait, landscape and square.

Examples

Measuring a page

const page = document.querySelector("pdf-page");
page.addEventListener("render", () => {
  const { width, height, aspectRatio } = page.image.metrics;
  console.log(width, height, aspectRatio); // 612 792 "612 / 792"
});

Specifications

Not part of any specification. <pdf-file> and <pdf-page> are autonomous custom elements defined by WebPDF.pro.

Browser compatibility

	desktop					mobile
	Chrome	Edge	Firefox	Opera	Safari	Chrome Android	Firefox for Android	Opera Android	Safari on iOS	Samsung Internet	WebView Android	WebView on iOS
`metrics`	125	125	153	111	18	125	153	83	18	27	125	18

: Full support