PNG uses lossless compression and supports transparency. A typical JPG export uses lossy compression and does not keep a transparent background. Neither format is best for every task.
A practical format choice
For a photograph without transparency, try JPG and inspect the result. For a screenshot with small text or a graphic with a transparent background, start with PNG. If a form requires one format, prepare a copy in that format and check it at the intended display size.
PNG to JPG: what changes?
In ShrinkBeam’s image converter, transparent pixels become white when exporting JPG. The quality setting can reduce fine detail. Download and compare text, logos and edges before using the new copy.
JPG to PNG: what does not change?
A PNG copy cannot restore detail missing from the JPG source. It may also be larger. Use conversion to meet a format requirement, not as a promise to improve a compressed photograph.
When the file is still too large
- Check the actual output bytes after processing.
- Use the resize tool if the destination permits fewer pixels.
- Try a lower JPG quality or a different accepted format.
- Keep the original and inspect the final download for readability.
Lossless format is not an unchanged image
Shrinking pixel dimensions removes image detail even when the output is PNG. A different crop also changes the image. Compare the result of the whole operation, not just the compression label.
Your next step
The tools process selected files locally. Keep your original and check the download.
Sources
Reviewed on October 8, 2026.