AVIF format explained: How to open and convert these files

What is AVIF?

AVIF (AV1 Image File Format) stores still images using compression derived from the AV1 video codec. The format supports lossy and lossless compression, transparency, HDR, wide color gamuts, and higher bit depths. It often compresses photographic content efficiently, although results depend on the image, encoder, quality target, and features being preserved.

File size depends on the test

AVIF can be smaller than WebP or JPG at a similar visual quality, but no percentage applies to every image. Photographs, illustrations, text, transparency, encoder versions, and quality settings can change the result substantially. Compare representative files at the quality your site needs before choosing a format.

Why AVIF compatibility is narrower than WebP's

AVIF is newer, and format support takes time to spread through the entire software ecosystem: browsers, operating systems, photo viewers, editing tools, and everything in between. Every major modern browser now supports AVIF for viewing images on the web, but plenty of desktop software, older devices, and offline tools haven't caught up yet. This is the same compatibility curve WebP went through in its own early rollout, a few years ago.

Where you'll run into AVIF files

• Saving images from performance-conscious websites: sites chasing every bit of load-time improvement have started serving AVIF to browsers that support it.
• Some newer phone cameras and apps: a handful of devices and photo apps have started offering AVIF as a storage option, similar to how iPhones defaulted to HEIC.
• Design and stock photo platforms experimenting with smaller formats: some are offering AVIF downloads to reduce their own bandwidth costs.

When an AVIF file will not open

An older viewer or editor may not include an AVIF decoder. Try the file in an updated browser or another compatible application before assuming it is corrupt. If several current tools reject it, the download may be incomplete or the file may use a feature that a particular decoder does not support.

AVIF and HEIC create a similar compatibility problem

Both formats can arrive in a workflow that expects JPG or PNG. HEIC became common through Apple devices, while AVIF is frequently encountered in web delivery and image optimization. Conversion can solve an immediate compatibility problem, but the destination format should match the content: JPG for ordinary photographs, PNG when transparency or lossless output matters.

AVIF vs WebP vs JPG at a glance

	AVIF	WebP	JPG
Relative file size	Smallest	Small	Largest
Software support	Growing, still limited	Broad	Universal
Best for	Cutting-edge web performance	General web use	Maximum compatibility

Choose a compatible destination format

Converting to JPG or PNG broadens compatibility, but neither format opens in literally every system. JPG is usually practical for photographs and does not preserve transparency. PNG can preserve transparency and lossless pixel data, although it may produce a much larger file. Standard conversions can also discard HDR, high bit depth, animation, color information, or metadata.

Questions to ask before converting AVIF

Is AVIF better than WebP? By most measures of compression efficiency, yes, slightly, but WebP currently has broader software support, so which one is "better" depends on whether file size or compatibility matters more for your situation.

Will AVIF eventually replace JPG the way WebP is trying to? It's trending that direction as support spreads, but JPG's near-universal compatibility means it won't disappear from general use anytime soon.

Does converting AVIF to JPG reduce quality? It can. JPG requires lossy encoding and cannot preserve every AVIF feature. Inspect gradients, fine texture, transparency, and HDR content after conversion.

Keep the AVIF original when possible. A converted copy is useful for compatibility, while the source preserves the format's full image data and features for future use.