Format choice matters
Converting an image changes how its pixels are stored. It does not automatically improve detail. The best format depends on transparency, visual content, compatibility and the intended destination.
JPG, PNG and WebP compared
JPG
JPG uses lossy compression and has broad compatibility. It works well for photographs but cannot store transparency. Repeated saves may accumulate artifacts.
PNG
PNG preserves pixels losslessly and supports alpha transparency. It is excellent for interface elements and screenshots, but detailed photographic PNG files can be large.
WebP
WebP supports both lossy and lossless modes plus transparency. Modern browsers support it widely, making it a useful web output when legacy software is not a constraint.
SVG, HEIC and PDF boundaries
SVG is a vector format, but wrapping a raster PNG in an SVG container does not magically trace it into vector paths. HEIC support depends on the included browser decoder. PDF-to-image conversion renders each page to pixels, so searchable text in the original PDF becomes part of an image.
When converting transparency to JPG, select a background color because JPG has no transparent channel.