AVIF is a modern image format based on the AV1 video codec. It supports lossy and lossless compression, transparency, HDR and wide colour, often at a smaller file size than JPEG or WEBP. Recent versions of macOS can open AVIF files directly; older apps and upload forms may require a JPEG or PNG copy.
Being royalty-free is the part that matters commercially, and it is why AVIF is spreading across the web while HEIC stays mostly inside Apple's world. It also handles transparency and wide colour, which JPEG cannot do at all.
How to open an AVIF file on a Mac
Recent versions of macOS decode AVIF at the system level, so Preview opens it, Quick Look previews it, and Safari displays it on a page. If yours does not, the limitation is your macOS version rather than the file, and the fix is either an update or a converter that carries its own decoder.
Image Converter reads whatever the Mac it runs on can read, and it asks the system that question at launch rather than promising a list. On a Mac that decodes AVIF, it converts them like anything else. On one that does not, it says so on the row instead of failing halfway through a batch.
When to convert AVIF to JPG or PNG
Plenty. Many desktop editors, most document and presentation software, a lot of content management systems, and a good number of upload forms. AVIF has the problem WEBP had five years ago and HEIC still has: the format is excellent and the software around it has not caught up. In that situation, converting to JPEG is not a downgrade. It is the price of being able to use the picture.
FAQ
AVIF or WEBP: which is better?
AVIF usually produces a smaller file at the same quality, particularly for photographs, and it handles wide colour and high dynamic range properly. WEBP is older and supported in more places. On the web today, most people serve AVIF with a WEBP or JPEG fallback.
Is AVIF better than JPEG?
Technically, by a wide margin: much smaller files, real transparency, wide colour, no visible blocking at low bitrates. Practically, JPEG is the one format that opens absolutely everywhere, which is why converting to it is still the thing people need to do.
Can I convert AVIF without uploading it somewhere?
Yes, and you should prefer to. Most AVIF converters you find by searching are websites, which means the picture leaves your machine, sits on a server you know nothing about, and is subject to whatever that site's retention policy says. A converter that runs on your Mac carries none of those questions.
Does converting AVIF to JPEG make the file bigger?
Almost always, and often by a lot. AVIF is very efficient, so the same picture stored as JPEG needs considerably more bytes. You are converting for compatibility, not to save space.
