PNG stores exactly the pixels it is handed, which is what you want before editing something over and over. Every JPEG save throws a little more away, and PNG throws away nothing. The size goes the other way: a photograph as a PNG is usually several times larger than the JPG was, and both numbers are printed once the conversion finishes.
This page loads no libraries at all. The work is done by the browser itself. Your file is read on your own machine and never sent anywhere. Open your browser’s network tab and watch while you use it.
No. PNG is able to store transparency, but a JPG has none to bring across, and nothing on this page removes a background. What you get is the same solid picture in a different container.
No. Whatever the JPEG already discarded is gone for good. What the PNG does is stop any further loss, so editing and saving again does not keep degrading the picture.
No. The picture is drawn onto a blank canvas and written out fresh, so only the pixels cross over. The EXIF block with the date, the camera model and any GPS position does not come with it.
No. The page takes one file per run: drop several and the first one is the one that gets converted. Run it again for the next.
Everything here is free and works the same way, in your browser.
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