AVIF file format
AV1 Image File Format
AVIF is a modern format based on the AV1 video codec. It often produces files about half the size of JPG with fewer artefacts, and supports transparency and HDR.
| Property | AVIF |
|---|---|
| File extensions | .avif |
| MIME type | image/avif |
| Introduced | 2019 by Alliance for Open Media |
| Compression | Lossy or lossless (AV1) |
| Transparency | Yes — full alpha |
| Animation | Yes |
| Colour depth | 8, 10 or 12-bit, HDR |
| Support | Chrome 85+, Firefox 93+, Safari 16+, Edge 121+ |
| Best for | Fast websites, hero images, photo galleries |
What is an AVIF file?
AVIF (AV1 Image File Format) was finalised in 2019 by the Alliance for Open Media, a group including Google, Mozilla, Microsoft, Netflix and Apple. It stores images compressed with the intra-frame tools of the royalty-free AV1 video codec inside a HEIF container — the same container family used by Apple's HEIC.
AVIF supports 8, 10 and 12-bit colour, HDR, wide colour gamuts, full alpha transparency and image sequences. In typical web tests it delivers files around 50% smaller than JPG and 20–30% smaller than WebP at similar visual quality, with notably less banding in skies and gradients.
Strengths and weaknesses of AVIF
AVIF's compression is the best of any format browsers widely support: Chrome (since 2020), Firefox (2021), Safari 16 (2022) and Edge (2024) all display it. It's royalty-free, unlike HEIC.
Encoding is slow — often seconds per image rather than milliseconds — and many desktop apps, older phones and Windows installations without the AV1 extension can't open AVIF files yet. Very fine text and 1-pixel lines can also soften at low quality settings.
When should you use AVIF?
Use AVIF to deliver photos and large graphics on modern websites, ideally with a WebP or JPG fallback via the HTML picture element. Avoid it for files you'll send to people or print, where JPG and PNG remain safer.