Why convert AVIF to JPG at all?

Compatibility. AVIF is the better format technically, but if the software opening the file does not support it, a slightly larger JPG that works beats a smaller AVIF that does not.

Does the image get resized?

No. The pixel dimensions are identical before and after; only the way the pixels are encoded changes.

What about transparency?

JPG has no transparency channel, so any transparent area is placed on white. If you need to keep it, convert to PNG or WEBP instead.

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AVIF to JPG

AVIF to JPG — for the software that has not caught up.

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