Short answer: open the .avif in a browser-based converter and download the JPG — no install, nothing uploaded. On a Mac you can also open it in Preview and use File → Export → JPEG. The only real decisions are the JPG quality (80–90 is the sweet spot) and the background color, because JPG has no transparency.
What AVIF is, and why you have one
AVIF is an image format built on the AV1 video codec — the compression technology behind modern video streaming, applied to still images. It stores photos 30–50% smaller than JPG at the same visual quality, which is why CDNs serve it and some cameras and apps save in it. Chrome, Firefox, and Safari all open AVIF now, so the files usually arrive quietly — a download or a saved image that picked the format the site served.
Why convert to JPG at all
Because the rest of the world hasn't caught up. Older desktop editors, upload forms that whitelist file extensions, office software, and print pipelines often don't recognize .avif — the file won't open, or the form rejects it outright. JPG is the universal fallback: everything reads it, everywhere.
The three ways to convert
- Browser converter: drop the file in, pick a JPG quality, download. The conversion runs locally in your browser — nothing is uploaded, which matters for personal photos.
- Mac Preview: open the .avif, then File → Export and choose JPEG. Built in on recent macOS, no extra software needed.
- Windows: the Photos app needs the AV1 Video Extension from the Microsoft Store to open AVIF at all. If you'd rather not install it, the browser route skips the problem entirely.
The traps
- Transparency silently becomes a color: JPG has no alpha channel, so transparent pixels get filled — usually white. If your AVIF has transparency that matters (a logo, an icon), pick the background fill deliberately — or convert to PNG instead.
- Quality 100: enormous files with no visible gain over 90. 80–90 is the sweet spot.
- Converting one file at a time: queue every AVIF and download a single ZIP instead of repeating the same steps per file.
- Converting for a website: you may not need to — serve AVIF with a JPG fallback (see below) and let the browser choose.
Batch it — and a fallback for the web
Converting one file at a time gets old fast. Queue every AVIF at once and download the results as a single ZIP. And if you're putting images on a website rather than converting for compatibility, you may not need to convert at all — serve AVIF with a JPG fallback and let the browser choose:
<picture>
<source srcset="photo.avif" type="image/avif">
<img src="photo.jpg" alt="A photo that works everywhere">
</picture>Try it
Drop your .avif files into the AVIF Converter — batch conversion, quality control, and a background fill for transparency, all in your browser with nothing uploaded.