What is a transparent PNG?
PNG can store an alpha channel: pixels may be fully or partly transparent. That lets logos and cutouts sit on any slide or storefront background.
JPG does not support transparency—exporting a cutout as JPG fills empty areas with a solid color (often white or black depending on the tool).
Use PNG (or WebP with alpha) when you need see-through regions; use JPG when you need smaller photo files without transparency.
File size trade-off: photographic PNGs are large. For photos without alpha, convert to JPG or WebP after editing. Keep transparent PNG masters for logos and product cutouts.
In e-commerce, many main-image rules want a flattened pure-white JPG even if you edited as a transparent PNG. Composite deliberately rather than uploading a checkerboard-looking asset.
Test your PNG on dark and light UI chrome so semi-transparent fringes do not surprise you after publish.
Related tool: PNG to JPG