Create a PNG without mistaking conversion for image repair
JPG to PNG is useful when an editor or exchange process specifically needs a PNG file. It is not a sharpening or restoration feature. The pixels decoded from a JPEG may already contain compression artefacts; PNG cannot undo them. This workspace creates a genuine PNG with the requested display dimensions and normalized direction, so the download is more than a renamed JPEG.
Photographic content can become substantially larger when encoded as PNG. For a fast-loading web photograph, JPEG or WebP may be more suitable. PNG is useful for retaining the decoded pixels in a lossless format during later editing, not for guaranteeing a small file. Begin with the closest available original and avoid repeated lossy conversions when you need precise lines or detailed source material.
Worked example
Converting a 1280 by 720 JPEG without resizing produces a 1280 by 720 PNG. Blocks or blurred edges already present in the JPEG remain part of the decoded image. The PNG may be larger even though its visible detail looks similar. If your actual goal is a smaller website file, compare JPG to WebP or the general compressor instead.
Local processing and limits
One supported static image is processed at a time. The general input limit is 10 MiB and twelve million pixels; AVIF processing is limited to four million pixels. Unsupported animation, image sequences, HDR and unverified container features are refused. Large images need more memory even when their compressed file is small. A failed operation does not switch to a server-upload fallback.
The browser downloads its own application and codec resources from the same host. Your selected image, result, filename and metadata are not sent to an upload service. Images are not written to localStorage, IndexedDB or a service-worker recovery cache. Reloading the page leaves the image workspace empty. Downloaded files remain under your control; inspect them before sharing.