PNG or JPG: the transparency question decides it
WebP can convert to either PNG or JPG, and the right choice comes down to one question: does the image have transparency you need to keep? PNG is lossless and preserves an alpha channel exactly; JPG has no concept of transparency at all and compresses further by discarding detail. If the WebP is a logo, an icon, or anything with a transparent background, PNG is the only one of the two that keeps it that way.
Lossless in, lossless out (if that's what you started with)
PNG never loses quality once you have it - every pixel is stored exactly. What it cannot do is restore quality that was already lost earlier. WebP supports both a lossy mode (the default for most photos, similar to JPEG) and a genuine lossless mode. If your file was saved lossy, converting to PNG locks in whatever quality it already had rather than recovering anything; if it was already lossless, PNG preserves it pixel for pixel with no further loss at all.
Why the file gets bigger
| WebP | PNG | |
|---|---|---|
| Typical size | Smaller | 25–35% larger, often more |
| Transparency | Yes | Yes |
| Compression | Lossy or lossless | Always lossless |
| Support outside browsers | Inconsistent | Universal |
WebP was built specifically to be smaller than the alternatives it replaces, so converting to PNG is a straightforward trade: you give up some of that efficiency in exchange for a format literally everything from a 2005-era printer driver to the newest phone can open without asking questions.
Where WebP still doesn't work
Browsers have supported WebP for years, which is exactly why the gap is confusing - the problem is never the browser, it's everything else. Printer upload portals, older desktop image editors, some phone gallery and backup apps, and web forms with a fixed list of "acceptable" formats frequently reject WebP outright. PNG has had decades to become the safe default; that history is the whole reason it still matters.
If the image has no transparency and file size is more important than universal compatibility, JPG (available as the other output option here) usually makes more sense than PNG - it compresses further for photographic content, at a small quality cost.
A whole folder at once
Drop in as many WebP files as you have and each converts independently, with a single ZIP download once they are all done. There is no file count limit, since nothing is uploaded to a server that would need to handle the load.
Nothing is uploaded
Both the decoding and the re-encoding happen entirely inside your browser using canvas. The images never leave your device.