Convert PNG to WebP

No. A visible quality loss is not inevitable with WebP, but the result still depends on how the image is encoded. The conversion is mainly useful for compatibility and file-size goals, so keep the original PNG as the master if you need to avoid any generation loss.

Yes. PNG and WebP both support transparency through an alpha channel, so transparent areas can be carried into the WebP output. The conversion changes the image format and compression, not the fact that those source pixels were transparent.

Different images compress differently, so changing the file extension does not guarantee a smaller result. Photos, screenshots, and flat graphics have different compression patterns. Compare the actual output size and quality rather than assuming WebP will win for every source image.

No. WebP is common on the modern web, but an individual website or upload form can still restrict accepted formats. Check the receiving system first. If it only lists JPG or PNG, convert to the format it explicitly accepts instead.

Use WebP when you want a web-oriented image format that can combine compact files with transparency support. Keep PNG when the receiving software already handles it well. The strongest reason to convert is a real compatibility or size requirement in the next workflow.