Saved an image from the web and got a WebP that won't open? Convert it to a JPG that opens anywhere — many at once, nothing uploaded.
WebP is the image format Google introduced for the web. It can be lossy or lossless, it can carry transparency, and it can even animate, which is why so many sites now serve it by default. JPG is much older and much simpler: lossy only, no transparency, no animation. Its advantage is that practically every program, phone, photo kiosk and upload form accepts it. Converting WebP to JPG trades WebP's extra abilities for that compatibility, which is usually the whole point.
Your browser decodes the WebP, draws it onto a canvas and encodes a new JPG at the quality you choose. Three things can change on the way. Transparent areas are filled with white, because JPG has nowhere to store them. An animated WebP becomes a single still — its first frame. And because JPG is lossy, a second round of compression is added on top of whatever the WebP already had. At the Recommended setting that extra loss is rarely visible, but it is not zero. Metadata such as camera details or location is not copied into the new file, because the picture is redrawn rather than copied.
The three buttons are quality 62 (Smaller), 82 (Recommended) and 94 (High), and the slider runs from 40 to 100. For photos, Recommended is a sensible default. For screenshots or images with small text, High keeps edges cleaner. Use “Compare with original” in the preview if you are unsure, and remember that a converted file is named after the original with _conv and a .jpg extension, so the two never overwrite each other.
Everything runs inside your browser. Because the image never reaches a server, we cannot store it or look at it. That difference matters when the file is company material or a personal photo.