AVIF compresses an image roughly 20 percent smaller than WebP at the same quality, while WebP encodes several times faster and works in more places. Both are next-generation formats derived from video codecs: WebP from VP8 in 2010, AVIF from the newer AV1 in 2019. AVIF is the stronger compressor, with support for HDR and 12-bit colour. WebP is the pragmatic default, with broader software support and quicker encoding. This comparison covers where each format comes from, compression, encode speed, colour depth, browser support, transparency and animation, and which format wins for a given use.

Neither wins outright. AVIF produces the smallest files and the widest colour; WebP is faster to make and safer to serve today. Many sites offer both, listing AVIF first and WebP second, with a JPG or PNG fallback last, so every browser gets the best format it can read.

Where each format comes from

Both formats are stills pulled from video compression. WebP takes its coding from VP8, a 2010 Google video codec, so it is now well over a decade old and thoroughly supported. AVIF takes its coding from AV1, a 2019 royalty-free codec from the Alliance for Open Media, whose members include Google, Netflix, and Apple. AV1 is a generation ahead of VP8, which is why AVIF compresses harder but also demands more computing power.

Compression: AVIF wins

Compression favours AVIF because AV1 is newer and smarter. On the same photo at matched quality, AVIF lands about 20 percent smaller than WebP, and far smaller than JPG. AVIF also handles flat colour and gradients cleanly, avoiding the banding that shows in weaker formats. For the smallest possible file, AVIF is the winner, and the gap grows on images with large smooth areas.

The saving compounds on an image-heavy site. If WebP already cut your images a third below JPG, AVIF trims another fifth on top, so the total reduction versus the original JPG can approach half. For pages measured on Core Web Vitals, that is a meaningful speed gain.

Encode speed: WebP wins

Encoding is where AVIF pays for its compression. AV1 is computationally heavy, so AVIF encodes several times slower than WebP. That matters when a site processes thousands of images, generates them on the fly, or runs on limited server resources. WebP encodes quickly enough for real-time use, which is one reason it became the default. Decoding, what the browser does to display the image, is fast for both, so visitors feel no slowdown either way.

Colour depth and HDR: AVIF wins

Colour depth separates the two clearly. AVIF supports up to 12 bits per channel and HDR, so it holds wide-gamut and high-dynamic-range images that WebP cannot. WebP caps at 8 bits per channel, the same as JPG. For photography, modern wide-gamut displays, and HDR content, AVIF is the only choice of the two. On a standard 8-bit screen the difference is invisible, but on capable hardware AVIF shows colours WebP simply cannot store.

Transparency and animation

Both formats cover transparency and animation, so neither wins here. Each carries a full alpha channel, so a transparent logo stays see-through in either, and both support animated clips far smaller than GIF. AVIF's animation compresses tighter thanks to AV1, while WebP's is quicker to produce. For a simple animated graphic, either beats GIF decisively.

Browser and software support: WebP wins

Support is WebP's advantage. Every modern browser has read WebP for years, and a deep well of software, plugins, and CDNs handles it. AVIF support is now broad in browsers, including Chrome, Firefox, and Safari, but it trails WebP, and desktop editors, older systems, and some CDNs lag further behind. For a file that must open reliably today across mixed software, WebP is the safer bet.

File size in real terms

Real numbers make the trade concrete. A photo that is 400KB as JPG might land near 280KB as WebP and about 220KB as AVIF at the same quality. A transparent graphic that is 120KB as PNG could be 80KB as WebP and 60KB as AVIF. The exact figures depend on the image, but the order holds: AVIF smallest, WebP middle, legacy formats largest. Choose based on whether the extra 20 percent is worth AVIF's slower encoding and narrower support.

Decoding speed and how visitors feel it

Decoding, not encoding, is what a visitor experiences, and here the two formats are close. When a browser displays an image it must decode it, and both AVIF and WebP decode fast enough for smooth page loads. The heavy AV1 computation in AVIF lives on the encoding side, done once when the image is created, not every time it loads. So a visitor never pays AVIF's encoding cost; they only benefit from its smaller download.

This split matters for how you deploy each format. Encode AVIF ahead of time, in a build step or a CDN, and cache the result. Never encode it on every request, because that would tax your server for no visitor benefit. WebP is forgiving enough to encode on the fly, but AVIF rewards pre-generation.

Building the fallback in HTML

Serving both formats safely uses the picture element, which lets the browser pick the best source it understands. You list AVIF first, WebP second, and a JPG or PNG last. The browser reads down the list and loads the first format it can decode, ignoring the rest. A modern browser takes the AVIF, an older one falls to WebP, and an ancient one gets the JPG. No visitor sees a broken image, and each gets the smallest file their software allows.

Most content management systems and image CDNs build this markup for you, so you upload one file and the system generates the formats and the fallback chain. Doing it by hand is fine for a small site, but automation scales better across hundreds of images.

AVIF for photography and HDR

AVIF's colour advantage matters most in photography. Its 12-bit colour and HDR support hold the wide tonal range of a modern camera and the vivid output of an HDR display, neither of which WebP can store. A landscape with a bright sky and deep shadows keeps more detail in both as AVIF. On a wide-gamut screen, saturated reds and greens that WebP would clip stay true.

For everyday web graphics on standard screens, this advantage is invisible, since an 8-bit display cannot show the extra range. But for photography sites, HDR content, and high-end displays, AVIF is the only one of the two that does the image justice.

The server and tooling cost of AVIF

AVIF's compression is not free at the point of creation. Its slower encoding means higher CPU cost and longer build times, which adds up when a site generates thousands of images. Older image libraries and some editors also cannot write AVIF yet, so your tooling has to support it. WebP, by contrast, is handled by nearly every image library and encodes quickly, which keeps it the low-friction choice for now.

The practical takeaway is to weigh the extra 20 percent size saving against the encoding cost and tooling gaps. For a large media operation optimising every byte, AVIF earns its place. For a small site, WebP delivers most of the benefit with none of the friction.

Which format wins

Neither wins for every job. Choose AVIF for the smallest files, HDR, and wide colour when your tooling supports it and encode time is not a bottleneck. Choose WebP for fast encoding, wide support, and a safe default that works across more software today. The strongest setup serves both: AVIF first, WebP second, and a JPG or PNG fallback last, so each visitor receives the best format their browser can decode.

How to create these formats

Creating modern formats takes no heavy tooling for WebP. Our PNG to WebP converter runs in your browser, batches files, and adds no watermark. AVIF encoding is more demanding, so it is usually handled by an image CDN or a build step rather than a quick browser tool. For most sites, generating WebP now and adding AVIF through your CDN later is the practical path.

Frequently asked questions

Does AVIF slow down my website when it loads?

No. AVIF decodes fast; only encoding is slow, and encoding happens once when the image is made, not on every page load. Visitors only get the smaller download.

How do I serve AVIF with a WebP fallback?

Use the picture element. List AVIF first, WebP second, a JPG or PNG last, and the browser loads the first format it can decode.

Is AVIF worth it for a small website?

Often not yet. WebP delivers most of the saving with less friction, since AVIF's slow encoding and tooling gaps add cost a small site rarely needs.

Is AVIF better than WebP?

On compression, yes. AVIF is about 20 percent smaller and supports HDR. WebP encodes faster and has wider support, so it is the safer default today.

How much smaller is AVIF than WebP?

Around 20 percent smaller at the same quality, and much smaller than JPG, because AVIF uses the newer AV1 codec.

Why is AVIF slower to make?

Because AV1 encoding is computationally heavy. AVIF trades encode speed for better compression, which matters when processing images in bulk or on limited servers.

Does WebP support HDR?

No. WebP caps at 8 bits per channel, so it cannot store HDR or wide-gamut colour. AVIF supports up to 12 bits and HDR.

Which browsers support AVIF?

Chrome, Firefox, and Safari support AVIF, though adoption trails WebP and some CDNs and editors lag. Serve a WebP or JPG fallback for older clients.

Do both AVIF and WebP keep transparency?

Yes. Both carry a full alpha channel, so a transparent graphic stays see-through in either format, unlike JPG.

Is AVIF or WebP better for animation?

Both beat GIF; AVIF compresses tighter. AVIF animation is smaller, WebP is faster to make, so pick by whether size or encode speed matters more.

Should I use AVIF or WebP for my site?

Serve both. AVIF first for the smallest file, WebP second for compatibility, with a JPG or PNG fallback for the rest.

Will AVIF replace WebP?

Not soon. AVIF compresses better, but WebP encodes faster and has wider support, so both are likely to coexist for years, served together.

Can older browsers open AVIF?

Often no. AVIF support is younger than WebP's, so a JPG or PNG fallback is essential for visitors on older software.

AVIF and WebP are both next-generation formats built from video codecs, but AVIF compresses about 20 percent smaller and adds HDR and 12-bit colour, while WebP encodes faster and enjoys wider support. Both keep transparency and animation, so the choice comes down to whether you want the smallest file or the safest, quickest one. Serve AVIF first for size, WebP second for compatibility, and a JPG or PNG fallback for the rest. Create WebP in your browser with our converter above, and add AVIF through your image pipeline.

Quick reference: AVIF or WebP

Reach for AVIF when you want the absolute smallest file, when the image needs HDR or wide colour, and when your CDN or build step can pre-encode it without slowing every request. Reach for WebP when you want fast encoding, the widest software support, and a low-friction default that nearly every tool already handles. The strongest setup is not one or the other but both, served in order: AVIF first for size, WebP second for reach, and a JPG or PNG fallback last so no visitor is left with a broken image.

What comes after AVIF

Image formats keep advancing, and JPEG XL is the next contender, promising strong compression with lossless JPG transcoding. Its browser support is limited today, so it is not a practical choice yet. For now, AVIF and WebP are the two next-generation formats worth deploying, with JPEG XL worth watching. Building a fallback chain means you can add a newer format later without breaking older browsers, which is why the picture element approach is future-proof.