Images missing from your PDF? Lazy loading is the usual cause

We ran each lazy-loading pattern five times. Native lazy images near the top were usually blank; plain images never were.

Updated 11 October 2026 · 4 min read

Lazy loading delays images until a visitor scrolls near them. It speeds up web pages, but the converter doesn’t scroll, and in our tests it made images unreliable. Here is what we measured and how to fix it.

Left: a product catalogue in a PDF with three empty grey boxes where the product photos should be. Right: the same catalogue with all three photos. — The same catalogue with loading="lazy" (left, images missing) and loading="eager" (right).

Results

We converted each pattern five times and counted how often the image appeared in the PDF:

Pattern	Near the top	Far down the page
Normal `<img>`, no lazy loading	5 of 5	5 of 5
`loading="lazy"`	0 or 1 of 5	5 of 5
`loading="eager"`	5 of 5	not tested
JavaScript loader (`data-src` and IntersectionObserver)	5 of 5	0 of 5
Script that copies every `data-src` into `src`	5 of 5	5 of 5

The native results surprised us: images at the top of the page were the ones that went missing. The cause is timing. The PDF is made once the page has finished loading, and lazy images and loader scripts can start their downloads too late. The pattern matters less than the rule: lazy loading of any kind made the PDF unpredictable.

Fixes for HTML you control

Remove loading="lazy", or change it to loading="eager", on every image the PDF needs. Changing it with a script after the page loads didn’t help in our tests; it has to be in the HTML.
Turn JavaScript loaders off in the version you convert, or put the real address straight into src. If you can’t change the markup, this script at the end of <body> worked every time:

<script>
  document.querySelectorAll("img[data-src]").forEach(img => {
    img.src = img.dataset.src;
  });
</script>

Embed small images as data URLs, so there is nothing to download; see fonts and images in HTML to PDF.

For webpages you don’t control

When converting a public URL, you can’t change its HTML. If images are missing, try converting again. If they’re still missing, save the page’s HTML, remove the lazy loading, and paste it into the HTML Code tab with full image addresses.

Missing images that aren’t lazy

If an image address returns an error such as 404, the PDF is made without it. If its server can’t be reached at all, the conversion fails. Check that each image opens in a private browser window.