Drop AVIF images above, download JPGs. Everything converts in your browser, nothing is uploaded.
Why you have an AVIF: websites serve it because it packs the same picture into roughly half the bytes of a JPG, and pages built on it load faster. Right-click and save an image from a modern site and AVIF is often what lands in your downloads. The trouble starts afterwards: older editors, upload forms and plenty of Windows machines refuse to open it.
The quality slider: 90% is the default and visually identical in normal use. Lower it for email and chat, raise it if the JPG is heading into an editor. The per-file byte counts show what each setting costs.
Transparency: JPG has none, and transparent regions composite onto white. Keeping transparency means AVIF to PNG instead.
Size: the JPG comes out larger than the AVIF it came from, often by 30-60%. AVIF is the newer and tighter format, while JPG is the one everything opens. You are buying compatibility with bytes.
The AVIF is worth keeping as the master, since it holds the same picture in fewer bytes and a JPG can be made from it again whenever one is needed.
Batches drop at once and each file reports its own numbers.