A short history
AVIF (AV1 Image File Format) appeared in 2019, developed by the Alliance for Open Media — a consortium including Google, Netflix, Amazon, Mozilla and others formed to build royalty-free media codecs. It applies the still-frame coding of the AV1 video codec to individual images, and quickly became the format to beat for raw compression efficiency.
How it works
By borrowing AV1’s advanced intra-frame prediction, AVIF reaches noticeably smaller files than WebP or JPEG at the same visual quality, while also supporting HDR, wide colour gamuts, 10/12-bit depth, transparency and animation. The trade-off is speed: encoding AVIF is computationally heavy, which is why it’s slower and why some browsers can decode but not encode it.
When & how to use it
Use AVIF for large, bandwidth-critical images — hero banners, big photography — where its compression pays off most. Because support is ~95% (not yet universal) and encoding is slow, serve it inside a <picture> element with a WebP or JPEG fallback so every visitor still sees an image.
- Introduced in 2019 by the Alliance for Open Media.
- Built on keyframes of the royalty-free AV1 video codec.
- Best-in-class compression, plus HDR, wide gamut, transparency & animation.
- Encoding is CPU-heavy — great for delivery, slower to create.