Methodology
Tool Testing Methodology
How FreePNGtoJPG checks tool behavior, output, privacy claims, and limitations.
Verify format support
We check that the browser can decode the listed input and that the downloaded file uses the declared extension and MIME type.
Explain lossy changes
Pages call out transparency flattening, lossy compression, rasterization, and other transformations that can affect fidelity.
Confirm local processing
Browser-only privacy claims are tied to tools that actually process the image on the device.
Scope
These checks cover the web implementation and representative inputs. They are not a certification of every possible file, browser, device, or third-party service.