Compare three formats from one transparent original

transparent.png is 600×400 with a teal shape, a light gray edge and transparent background. white-background.png is its flattened white counterpart. Keep the same source for a format comparison.

1. Export transparent.png as PNG, JPG and WebP at 600×400 with the same crop. Record quality for lossy formats. After every change to batch format, background or watermark settings, click Apply settings & preview and wait for all outputs to finish before downloading.

2. Reopen all three downloads on light and dark backgrounds. Check extensions, actual media types and bytes.

3. Record transparency in PNG/WebP and the JPEG background, then choose using recipient support as well as size.

All three should remain 600×400. JPEG has no alpha channel; PNG and WebP can retain it with background preservation. Byte rankings apply to these encodings, not every possible image.

Importing white-background.png and saving PNG retains the existing white pixels. Changing an extension cannot recreate transparency. Return to the transparent original rather than blaming the target format for the flattened source.
