AVIF to JPG

AVIF spread through websites much faster than it spread through desktop software, and that gap is why most people end up here. You saved an image from a modern site and now Photoshop, Windows Photo Viewer, your phone's gallery app or a submission form will not touch it. Browsers are the exception rather than the rule: Chrome has decoded AVIF since version 85, Firefox since 93 and Safari since 16.4, which is precisely why this conversion can happen locally in your browser at all. JPG goes the other way — it is understood by essentially everything, at the cost of larger files for the same visual quality. If the file is just for your own use and your software cannot read AVIF, converting is far simpler than hunting for a codec.

This is the expected trade and worth being clear about. AVIF frequently achieves half the size of a JPG at matched quality, so going the other way roughly doubles it. You are buying compatibility with bytes. If size genuinely matters for the destination, keep the quality slider around 0.85 rather than pushing it to maximum — the difference is hard to see and the saving is significant.

AVIF supports an alpha channel and high dynamic range; JPG supports neither. Transparent areas are filled with a background colour you choose. HDR images are tone-mapped down to standard range by the browser during decoding, which for a bright, high-contrast photograph can visibly flatten the highlights. If either matters, convert to PNG instead — it keeps the transparency, though it cannot keep HDR either.

AVIF wraps the AV1 video codec, which browser vendors adopted early and aggressively because it is royalty-free and good for video streaming. Desktop image software has taken longer, since it means integrating a whole video codec to display a still picture. That is the whole explanation for the odd situation where a web page shows the image fine and double-clicking the saved file does nothing.

AVIF wraps the royalty-free AV1 video codec into a still-image format, and it compresses harder than anything else in mainstream use — frequently half the size of a JPG at matched quality, with transparency and high dynamic range on top. Browsers decode it well (Chrome since 85, Firefox since 93, Safari since 16.4), but support thins out fast beyond them: many image editors, older operating systems and most print workflows still cannot open one.

JPG (also written JPEG) has been the default photograph format since 1992. It uses lossy compression tuned for the way human vision works — discarding fine colour detail the eye barely registers — which is why a photo saved as JPG can be a tenth the size of the same image as PNG. The trade-off is that it has no transparency channel and that every re-save degrades the image slightly, so it suits finished photographs rather than working files.