Large images without srcset

Low priorityImages

Images 600px or wider have no srcset, so phones download the full desktop-size file.

What triggers this issue

• Images with a width of 600 or more and no srcset attribute.

Why it matters

A phone screen might need a 400px image while the file is 1600px wide: four times the pixels, downloaded for nothing.

How to fix it

1. Provide several sizes with srcset and tell the browser how wide the image displays with sizes.
2. Most CMSs and image CDNs can generate the sizes automatically.

<img src="photo-800.jpg"
     srcset="photo-400.jpg 400w, photo-800.jpg 800w, photo-1600.jpg 1600w"
     sizes="(max-width: 600px) 100vw, 800px"
     alt="…" width="800" height="600">