Convert WebP to PNG

What a WebP to PNG conversion actually does

It changes the container and leaves the picture alone. PNG stores whatever it is handed, pixel for pixel, so what comes out the far side is precisely what your browser saw when it decoded the WebP — no better, no worse, no sharper. That distinction matters because "lossless" reads like a promise of quality, and it is not one. It is a promise of faithfulness. If the WebP you have was compressed with detail thrown away, that detail is not coming back, and the PNG will now preserve its absence exactly.

Which is fine, because quality is almost never why anyone lands here. The reason is that something refuses to accept the file. Save an image from a modern site and this is what you get, because the site was serving WebP to keep its pages light — and then Photoshop CS6, a print shop's intake form, a marketplace listing tool or a university submission portal turns around and says no. Renaming the extension does not help, and it is worth knowing why, since it is what most people try first. Only the label changes. A decoder reads the first twelve bytes, sees the RIFF header with a WEBP tag behind it, and declines regardless of what you called the file. Some report that as corruption, which is misleading: nothing is damaged, the program was simply never taught this format.

The file gets bigger, and the multiplier is not a constant

Everyone knows the PNG will be larger. Almost nobody guesses by how much, and the spread is enormous. Measured on this tool's own test files: a 1200 by 900 photograph went from 83 KB to 1.7 MB, twenty times over. A small animation went from 6.2 KB to 9.2 KB, barely half again. A 400 by 400 badge went from 1 KB to 7.6 KB. Same conversion, same code, multipliers of 1.5, 7 and 21.

The reason is that PNG's compression works on repetition and flat regions, and photographs have neither. Every blade of grass is a fresh instruction to store. So the estimate above the button is not a rule of thumb applied to your file size — sixteen tiles are cut from across each picture at full resolution, assembled into one sheet, encoded as PNG for real, and the resulting bytes per pixel multiplied by your output dimensions. It is still an estimate, and an unevenly detailed picture will move it, but it is arithmetic on a genuine encode rather than a plausible-sounding fraction.

If the number that comes back is uncomfortable, the honest options are to cap the longest side before converting, or to reconsider whether you need PNG at all. Software that rejects WebP usually accepts JPG, which is a great deal smaller — that route isWebP to JPG, and it costs you a second round of lossy compression instead of costing you megabytes.

Transparency is the easy part in this direction

Both formats carry an alpha channel, so a transparent background copies straight across and there is nothing to decide. No color picker appears, because there is no flattening to configure — a control with no effect is worse than no control. This is the one respect in which converting to PNG is strictly better than converting to JPG, where transparency has nowhere at all to live and has to become a solid fill, which is where black rectangles around logos come from.

An animated WebP arrives as a single frame

WebP holds animations, in much the way GIF does. PNG has an animated form too, called APNG, and every browser can display one — but none of them will write one from a canvas, and a canvas is the encoder doing the work here. So the animation does not survive: you get frame one and nothing else.

Before anything is encoded, the container is parsed and the frame count lifted straight out of it, so a file that moves is labeled as one while you can still change your mind. Seeing "Animated, 8 frames" is the moment to decide whether a still image is what you wanted. If it is not, moving pictures belong somewhere else entirely: turn the motion into an MP4, or shrink an existing GIF instead of flattening it.

Where the work happens

Both halves of this conversion already live on your machine. Decoding WebP is why the file previews at all, and PNG encoding is built into the same canvas API every browser ships. So the pictures stay on your device from the moment you drop them until you save the results; nothing is transmitted, because nothing needs to be. No queue, no account, and no ceiling on file size other than the memory your own device is willing to give the tab.

One consequence is worth stating plainly rather than discovering later: metadata does not make the trip. Any color profile, EXIF block or copyright field in the source is absent from the PNG, because the encoder is handed pixels and nothing accompanies them. For images pulled off the web that is generally welcome. When the source is your own camera roll and the shooting data matters, keep a copy of what you started with.

Going the other way — shrinking pictures for a site rather than opening them —PNG to WebP is the same machine pointed in reverse, and it has a choice this page does not need to offer.