AVIF vs WebP: Which Next-Gen Format Should You Use?

Two Modern Formats, One Decision

For years the question was simply "JPEG or PNG." Now there are two newer formats competing to replace both: WebP, released by Google in 2010, and AVIF, derived from the AV1 video codec and standardized in 2019. Both compress dramatically better than JPEG, both support transparency, and both are supported by every current major browser. So which one should you actually use? The honest answer is that it depends on what you are optimizing for — and for most people in 2026, the safe default is still WebP, with AVIF as a powerful extra.

How They Compare on File Size

AVIF is the more aggressive compressor. On typical photographic content, a well-encoded AVIF file is roughly 20–30% smaller than the equivalent WebP at the same perceived quality, and 40–50% smaller than a JPEG. The advantage comes from AV1's sophisticated intra-frame prediction, larger and more flexible block sizes, and better entropy coding — the same machinery that makes AV1 an efficient video codec, applied to a single still frame.

WebP, by contrast, is built on the older VP8 codec. It still beats JPEG comfortably — 25–30% smaller for photos — but it does not reach AVIF's efficiency, especially at low bitrates where AVIF preserves smooth gradients and fine texture noticeably better.

Where the gap narrows is on small images and flat graphics. For a 40 KB icon or a simple logo, the two formats land within a few percent of each other, because there are simply fewer bytes to optimize. AVIF's advantage is largest on big, detailed photographs — exactly the hero and content images that dominate page weight.

How They Compare on Quality

At the same file size, AVIF generally looks better, and it degrades more gracefully. When you push a JPEG too hard it produces blocky 8×8 artifacts; when you push WebP too hard it tends to smear fine detail. AVIF, pushed to the same low bitrate, holds gradients and edges together longer before it visibly breaks down, which is why it is particularly good for images with large smooth areas like skies, skin, and studio backgrounds.

AVIF also supports a wider color gamut and high dynamic range, plus 10- and 12-bit color depth. For most web work that is irrelevant, but for photography portfolios and HDR content it is a genuine advantage WebP cannot match.

Browser and Ecosystem Support

This is where WebP still wins on safety. WebP has been universally supported in browsers since 2020 and is handled by virtually every image editor, CMS, and CDN. AVIF reached full support across Chrome, Firefox, Safari, and Edge by 2024, so browser coverage is now broad — but the surrounding ecosystem lags. Some older editors, certain email clients, and a few content management systems still do not read or generate AVIF. As with WebP before it, the browser caught up first and the long tail of tools is still catching up.

The practical consequence: for images you serve on a modern website with a proper fallback, AVIF is safe. For a single file you email, hand to a colleague, or upload to a system you do not control, WebP — or even plain JPEG — remains the more predictable choice. For the full cross-client picture, see reducing image size for email.

Encoding Speed: The Hidden Cost

AVIF's compression efficiency is not free. Encoding an AVIF image is significantly slower than encoding WebP — often several times slower at high effort settings, because the encoder is exploring a much larger space of possible block arrangements. For a single image this is a non-issue; you wait a second or two longer. For a server batch-processing thousands of images on every upload, that difference compounds into real CPU cost and latency.

This is the main reason many sites still reach for WebP first: it is fast enough to encode on the fly, while AVIF is often better suited to images you process once and serve many times. Decoding, on the other hand, is fast for both — the viewer never pays AVIF's encoding penalty.

The Right Way to Use Both

You do not have to choose just one. The modern best practice is to offer multiple sources inside a `<picture>` element and let the browser pick the best one it supports. The browser reads the sources in order, takes the first format it understands, and ignores the rest. Put AVIF first, WebP second, and a JPEG fallback last. A browser that supports AVIF downloads the smallest file; one that only supports WebP gets the next best; anything older still gets a working JPEG. Nobody gets a broken image, and everybody gets the smallest file their browser can handle.

A Worked Example: One Hero Image, Three Formats

Take a 1600×900 photographic hero image — a landscape shot with sky, water, and foliage. Encoded at equivalent perceived quality:

• JPEG (MozJPEG, q=80): about 180 KB. The universal fallback.
• WebP (q=80): about 130 KB. Roughly 28% smaller than the JPEG, supported everywhere.
• AVIF (medium effort, equivalent quality): about 95 KB. Roughly 27% smaller than the WebP again, and about 47% smaller than the JPEG.

Served through a `<picture>` element with all three sources, an AVIF-capable browser pulls 95 KB, a WebP-capable one pulls 130 KB, and the rare older client still gets the 180 KB JPEG. The mobile user on AVIF saves nearly half the bytes of the JPEG baseline — on the exact image that drives the page's Largest Contentful Paint score. For target sizes per page region, see best image sizes for web performance.

Common Misunderstandings

• AVIF is not always smaller than WebP. On small images, flat graphics, and already-noisy content, the two land close together. The big wins are on large, smooth photographs.
• AVIF support being "in all browsers" does not mean every tool reads it. Editors, email clients, and some CMSes still lag. Use it on the web with a fallback, not for files you send around.
• You do not pick one format for the whole site. The `<picture>` element lets you serve AVIF, WebP, and JPEG from the same markup, so there is rarely a reason to commit to a single format.
• A "next-gen" format will not fix a badly sized image. Serving a 4000-pixel AVIF into a 400-pixel slot still wastes bytes. Resize first, then choose a format. See how image compression works.

Frequently Asked Questions

Q: Should I switch my whole site from WebP to AVIF?

Not switch — add. Keep WebP as a source and add AVIF ahead of it in a `<picture>` element. Browsers that support AVIF take the smaller file; everything else falls back to WebP, then JPEG. You get AVIF's savings with zero compatibility risk.

Q: Is AVIF good for graphics and logos, or just photos?

It works for both and supports lossless mode plus transparency, but its biggest advantage is on photographs. For flat graphics and logos, lossless WebP or PNG is often just as small and faster to produce. See JPEG vs PNG vs WebP for the graphics-versus-photo decision.

Q: Why is AVIF encoding so slow?

Because it inherits AV1's exhaustive block-partitioning search — the encoder tries many ways to divide and predict each region to find the smallest result. That search is what makes the files small, and also what makes encoding slow. Decoding is fast, so viewers never pay the cost.

Q: Can I use AVIF in email?

No, not reliably. Email-client support for AVIF is even worse than for WebP. Stick to JPEG and PNG for email — see how to reduce image size for email.