PNG and JPG solve different problems, and converting one into the other means trading something away for a smaller file. PNG is lossless — every pixel is stored exactly as created — and it supports a full alpha (transparency) channel, which is why it is the default format for screenshots, app icons, and graphics meant to sit cleanly over another background. JPEG uses lossy, block-based compression that groups pixels into small squares and discards detail the eye is less likely to notice, and it has no transparency channel at all. Converting a PNG to JPG means accepting both trade-offs at once: some fine detail is thrown away permanently, and any transparent area in the source image gets filled in with a solid color — white, on this tool — before the file is saved.
JPEG quality on this converter runs from 40% up to 100%. At the high end, compression artifacts are essentially invisible even on close inspection. Drop below roughly 70% and you start to notice blockiness around sharp edges and banding across smooth gradients — this shows up faster on screenshots with crisp UI elements or flat-color diagrams than it does on genuine photographs, because JPEG's compression algorithm was designed around photographic noise patterns, not clean vector-style graphics. It is also worth knowing that quality loss compounds with repeated re-saving: a JPEG that has been opened, edited, and re-exported several times looks visibly worse than one saved once at the same quality setting, because each pass re-applies lossy compression on top of artifacts the last pass already introduced.
Because JPEG has no alpha channel, there is no way to carry transparency through this conversion — any transparent or semi-transparent pixel in your PNG is composited onto solid white before the JPEG is written. If you need a smaller file than PNG but still want to keep transparency intact, WebP is the better target: it supports both lossy and lossless modes alongside a full alpha channel, and the PNG to WebP tool on this site handles exactly that case.
The usual reason to make this conversion is file size. A PNG screenshot or graphic exported at high resolution can run several times larger than a JPEG of the same pixel dimensions, and that difference matters once you are attaching images to email (many providers cap total attachment size well below what a folder of PNGs adds up to), embedding photos on a web page where every extra kilobyte slows the load, or uploading to a platform — certain job application portals, print-on-demand storefronts, older content management systems — that accepts JPG uploads only and rejects PNG outright. Print bureaus in particular tend to standardize on JPEG for photographic output even when the original artwork or mockup was built as a PNG.
Need transparency preserved at a smaller size? PNG to WebP handles that case directly.
