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June 29, 2026 · 6 min read
Just as WebP became the go-to modern image format, a newer one arrived that compresses even harder: AVIF. If you're optimising images and squeezing every kilobyte matters, AVIF is now the format that gets you the smallest files. Here's what it is, how it compares, and whether it's the right choice today.
AVIF (AV1 Image File Format) is an image format based on AV1, a modern, royalty-free video codec. Because it borrows the compression technology from cutting-edge video, it's remarkably efficient at shrinking still images — noticeably more so than JPEG, PNG or even WebP.
Like WebP, AVIF is a do-everything format: it handles photographs, supports transparency, does both lossy and lossless compression, and even supports HDR and wide colour gamuts for richer images.
AVIF is typically about 50% smaller than a JPEG at comparable quality, and often 20% smaller than WebP. It's especially good with gradients, skies and dark scenes, where older formats show banding — AVIF keeps these smooth at very low file sizes.
In practice, an image that's 1 MB as a JPEG might be around 500 KB as WebP and 350–400 KB as AVIF. On an image-heavy page, that's a serious speed and bandwidth win.
AVIF isn't free of downsides. Encoding is slower and more CPU-intensive than JPEG or WebP, so converting large batches takes longer. And while it excels on photos and gradients, for very small graphics or simple icons the savings over WebP can be marginal — sometimes WebP or PNG is just as good.
There's also detail loss to watch for: pushed too hard, AVIF can smooth away fine texture in a way that looks slightly artificial. As always, compare before and after at your target size.
AVIF support has come a long way. All major browsers — Chrome, Firefox, Safari and Edge — now render AVIF images, so the large majority of your visitors will see them fine. It's no longer the experimental format it was a few years ago.
That said, support is still slightly behind WebP, and some older devices, apps and email clients can't open AVIF. So for the open web, AVIF is ready; for files you send or upload elsewhere, a JPEG or WebP is still the safer choice.
Use AVIF for images on your website when file size is your top priority and you can provide a fallback — serve AVIF first, with WebP or JPEG for the few browsers that need it. Most modern site platforms handle this automatically. For photography portfolios, e-commerce galleries and any image-heavy page, the savings are well worth it.
If you just want something lighter with the least hassle and broadest support, WebP remains the safe all-rounder. Want to try AVIF? Drop an image into our converter, choose AVIF as the output, and compare the size for yourself — everything runs in your browser, so nothing is uploaded.