Convert an image

No. Toolpit does not upload your file for processing — the tool runs as code in this browser tab, works on the copy your browser opened, and forgets it when you close the tab. You can check this yourself: open your browser’s network panel and run the tool. You will see the page, its scripts and the ads on the site, and — when you save, if you are signed in — one small request that charges 10 tokens to your account. None of them carries your file, its name or anything read from it, because file processing stays on your device.

Because this browser cannot encode it. Support for writing AVIF in particular varies between browsers, and rather than silently handing you a PNG with the wrong file extension, the tool checks first and tells you.

JPG has no transparency, so see-through pixels need a colour behind them. The tool asks you which one instead of defaulting to black, which is what a naive conversion produces.

JPEG for photographs that need to be small and to open anywhere. PNG when you need transparency, or for screenshots, logos and line art where sharp edges matter — it is lossless, so text stays crisp instead of growing halos. WebP when the destination supports it: it does both jobs and produces meaningfully smaller files than either, which every current browser reads.

PNG and WebP keep it. JPEG has no concept of transparency, so anything see-through is filled — with white unless you choose otherwise. That is the usual explanation when a cut-out logo suddenly gains a white box after conversion: the transparency was not lost by the tool, it is simply not something JPEG can represent.

Converting to PNG does not, since it is lossless. Converting to JPEG or WebP re-encodes the picture and discards some detail, which is the trade that makes them small — at high quality settings this is invisible at normal viewing size. Converting a JPEG to another JPEG loses a little again, so work from the best original you have rather than a copy of a copy.