What AVIF is — and why apps reject it
AVIF is the newest mainstream image format, built on the AV1 video codec. It compresses roughly 50% smaller than JPG at the same quality, supports transparency and HDR, and is what many large websites now serve. Your browser can display it — which is exactly how this converter works — but a long tail of software still can't: older editors, upload forms, office tools, print services.
When you save an AVIF from the web and something rejects it, convert it to WebP (small, modern) or JPG (opens absolutely everywhere) above.
AVIF vs WebP vs JPG
| AVIF | WebP | JPG | |
|---|---|---|---|
| Size at equal quality | Smallest | Small | Baseline |
| Transparency | Yes | Yes | No |
| Software support | Browsers, newest apps | Nearly universal | Universal |
| Encoding speed | Slow | Fast | Fast |
Rule of thumb: keep AVIF when a modern website is serving it automatically; convert to WebP or JPG the moment you need to edit, upload or share the file. Full breakdown in Best image format for websites.