Most of the Web's Images Are Still JPEG and PNG

Use a modern image format has been the web's most repeated performance advice for a decade. It is also the cheapest speed win available: swap a JPEG for a newer format and the same picture arrives a third lighter, with no visible loss. So a fair question is whether the web actually took the advice. We classified 435 million images to find out, and the answer is that it is switching, unevenly. WebP has arrived. AVIF is still waiting. The old formats are proving hard to kill.

Format is not a cosmetic choice. Images are the single largest contributor to page weight on most sites, so the bytes a site ships as JPEG instead of AVIF are the bytes that slow its loading, drain visitors' mobile data, and drag on the Largest Contentful Paint that Google has scored as a Core Web Vital since 2021. A site still running on legacy formats is, quite literally, in the slower half of the web.

Our snapshot comes from the HTTP Archive, the open dataset that crawls millions of real homepages and records every resource they load, giving a census-level view of what the web is actually made of. Across 435 million images on 15.7 million homepages, here is where the format transition stands, and how far it has moved in four years.

The figures come from the HTTP Archive's June crawls of 2022, 2024, and 2026, on mobile, covering site homepages. For 2026 we classified 435 million image requests across 15.7 million homepages by format from the archive's response metadata, and computed both each format's share of all images and its site-level adoption, where a homepage counts as using a format if it serves at least one image in it. For the trend we compared each format's share of all images across the three years, since crawl sizes differ. A small share of requests are unclassified and excluded.

WebP is the success story. It is now the third most common image format on the web, behind only JPEG and PNG, at 17% of all image requests, and at the site level 40% of homepages serve at least one WebP image. For a format that barely registered a few years ago, that is a genuine transition from supported to commonplace. AVIF is the format still waiting for its moment: more efficient than WebP and well supported in modern browsers, but sitting at just 4% of images and appearing on only 11% of homepages. If WebP is the present, AVIF is still the future.

The old guard is stubborn. JPEG (28%) and PNG (25%) together are more than half of every image on the web. Add GIF and legacy formats account for the bulk of all images. The GIF number deserves its own line: at 16% of images, a format from 1987 is still one image in six, long after animated GIFs should have become video and simple graphics should have become SVG or PNG. Combined, next-gen formats WebP and AVIF are 21% of all images, real progress but far from a takeover.

Four years ago the modern image format was a rounding error. In June 2022, WebP accounted for just 2.4% of all image requests, and AVIF for a tenth of one percent. By 2026 WebP is up to 16.6%, a sevenfold increase that carried it past GIF into the top tier of formats. Its growth accelerated: it roughly doubled between 2022 and 2024, then more than tripled between 2024 and 2026. The tipping point is recent.

AVIF is the more dramatic percentage story and the more cautious absolute one. It grew fortyfold, from 0.1% to 4.3%, with almost all of that movement in the last two years. That is a format going from does anyone use this to a real presence in a single crawl cycle. But 4.3% is still small: for every AVIF image on the web there are still about six JPEGs. AVIF is rising fast, and it is still early. Both are true.

Underneath the winners, the old formats give way at different rates. JPEG is in clear, steady decline, from 43% to 37% to 27%, losing share directly to WebP and AVIF, its natural replacements. PNG held flat through 2024 and then began to slip. GIF barely moved, sitting between 15% and 18% across the entire period, a reminder of how much of the web's image layer is inertia rather than optimization. The acceleration is not really about developers hand-converting images. It is about defaults: image CDNs and content platforms turning on automatic modern-format delivery flips a large batch of sites at once, which is why the growth compounds.

Each format's share of all image requests on mobile homepages, June of each year, HTTP Archive. Any next-gen format reaches 45% of sites.

If your images are still mostly JPEG and PNG, you are in the slower half of the web. Those two formats are 53% of every image loaded, and images are the heaviest thing standing between a page and a fast Largest Contentful Paint. Switching a JPEG to WebP typically cuts 25 to 35% of its bytes with no visible loss, and AVIF cuts more.

The fix is close to free because it is a default, not a hand-conversion job. Most image CDNs and many CMS plugins will auto-negotiate WebP or AVIF from the visitor's browser, which is exactly why WebP climbed sevenfold to 16.6% of all images in four years while developers did little by hand. Turn that default on and a whole batch of images gets lighter at once, source files untouched.

Reach for AVIF specifically. It sits at 4.3% of images and 11% of sites, so browser support is already broad while adoption stays low enough that using it puts you ahead of 89% of the web. Format is the page-weight lever with the best return per minute, and the 55% of sites still shipping only legacy formats are paying for bytes they do not need in both conversions and search rank.