snag.page

Every check · Loading

Image dimensions

perf/image-size

What it checks

Images without both width and height attributes.

Why it matters

The page jumps as they load, which counts against Cumulative Layout Shift.

How to fix it

  1. Give each img its width and height attributes; CSS can still resize it.
HTML
<img src="/photo.jpg" width="1200" height="800" alt="…">

Check a site for this and everything else: snag.page. More on loading: Compression Blocking scripts Lazy images Page weight Redirects Script caching