Why it happens
The JPG format has no alpha (transparency) channel. Every pixel must have a solid color, so transparent regions get flattened — to black in many editors, or white in others.
How to fix it
- Keep transparency: convert your JPG-bound image to PNG or WebP with the tool below; both support transparency.
- OK with a solid background: flatten onto white intentionally (our compressor fills transparency with white instead of black).
Tips
- Logos, stickers and cutouts should stay PNG/WebP, never JPG.
- Once a JPG has baked-in black, the transparency is gone for good — go back to the original PNG.