AVIF vs WebP: the next-gen image format comparison

Two generations of the same idea

WebP and AVIF are both examples of the same strategy: take the compression techniques built for video codecs, which have to squeeze a sequence of frames into as few bits as possible, and apply them to a single still image. WebP, released by Google in 2010, is built on VP8, an older video codec. AVIF, standardized around 2019 to 2020 by the Alliance for Open Media, is built on AV1, a considerably newer and more sophisticated video codec. That generational gap is the whole story behind why the two formats perform differently.

Compression: AVIF usually wins

Because AV1 is a newer, more advanced codec than VP8, AVIF generally compresses smaller than WebP at matched visual quality. Independent compression studies that test AVIF against WebP at the same quality level commonly find AVIF files around 20 to 30 percent smaller than WebP for the same image, on top of WebP's own already substantial savings over JPG. The gap varies by image content and by how aggressively each format is encoded, but the direction is consistent: AVIF is the newer, more compression-efficient of the two.

The trade-off: encoding cost and tooling

AVIF's better compression comes at a cost. Encoding an AVIF file is more computationally expensive than encoding a WebP file, so batch converting a large number of images to AVIF takes noticeably longer. Decoding is also somewhat heavier, which can matter on older or lower-powered devices. WebP has also simply been around longer, so more image editors, content management systems, and command-line tools support it natively, while AVIF support in some of that older tooling is still catching up.

Browser and platform support

Both formats are supported by every current major browser (Chrome, Firefox, Safari and Edge), so for a modern website, either is a safe choice for the browser side of things. The gap shows up off the web: because WebP has existed for over a decade, it is far more likely to open correctly in an arbitrary desktop image viewer, older editing software, or a random upload form. AVIF, being newer, is more likely to hit a tool that does not recognize it yet, which is exactly why AVIF to JPG and AVIF to PNG are common searches.

Which one should you actually use

If your goal is the smallest possible file size for images on a website you control, and your build pipeline or CMS supports it, AVIF is the better technical choice. If you want a single modern format that behaves predictably across the widest range of tools, browsers, and workflows today, WebP is the safer default. Many sites end up using both: AVIF where the pipeline supports it and the savings matter most, WebP everywhere else as a broadly compatible fallback.

Is AVIF always smaller than WebP?

Usually, but not universally. For most photographic content AVIF compresses meaningfully smaller at the same quality, though the exact gap depends on the image and the encoder settings used.

Why would I use WebP instead of AVIF if AVIF compresses better?

WebP has broader support in older editors, content management systems and third-party tools, and it encodes and decodes faster, which matters when converting large batches of images or displaying them on lower-powered devices.

Do I need to convert AVIF or WebP files before uploading them somewhere?

Only if the destination does not accept them. Most modern websites and apps handle both formats fine; older software, some print workflows, and some upload forms are the main places you will still need a JPG or PNG instead.