AVIF (and modern image formats)
AVIF (AV1 Image File Format) is an “open, royalty-free” modern image format — the most direct lever on the single biggest slice of page-weight. The Web Almanac put images at ~1,054 KB, the largest component of the median page; better image compression is therefore the highest-leverage byte saving. Source: Wikipedia.
The compression advantage
Per Netflix testing, “AVIF showed better compression efficiency than JPEG as well as better detail preservation, fewer blocking artifacts and less color bleeding” — and it beats WebP too. Browser support is now broad: “all the major web browsers (over 93% … by use)” (Chrome 85, Firefox 93, Safari 16, Edge 121). So the legacy-JPEG default is now a defensible budget target to replace.
Why it matters here
This is the concrete mechanism behind the wiki’s page-weight thesis: serving AVIF/WebP instead of
JPEG/PNG (with <picture> fallbacks) cuts the dominant byte category — exactly the kind of
efficient delivery the cross-wiki page-weight-vs-architecture
debate says drives real-world performance. Format choice, not just fewer images.
Related
page-weight · web-almanac-page-weight-2024 · performance-budget · bundle-size · core-web-vitals