Images · 2 tools
Work on a picture, not a document
The only group here that never produces a PDF. A picture goes in and a picture comes out, because the two things people most often cannot do with a photograph — open it, and send it — have nothing to do with documents.
The tools
Why a PDF site has image tools
Because the promise was never PDF, it was that your file stays on your device. The photograph somebody cannot open is usually a photograph of paperwork, and the one they cannot attach is usually a photograph of a receipt. Sending either to a converter's server to fix a format problem is the trade this site exists to refuse.
The decoding belongs to your device
There is no image decoder in this bundle and there is not going to be one: a WebAssembly build of libheif is well over a megabyte, downloaded by everybody to serve the minority whose browser cannot already do the job. The browser's own codecs do the reading, which means HEIC works on iPhone, iPad and current Safari and generally does not on Windows. The tool says so, with the device that can, rather than failing into a spinner.
What a smaller file costs
Quality, always, and the only question is how much for how little. So the compressor searches for the largest quality that still fits the size you asked for, rather than handing you a slider and the arithmetic. When re-encoding would return a bigger file — which is what happens to an already-optimised JPEG — you are given your original back and told why.
What is not here yet
Resizing to a chosen width, cropping, PNG to JPEG and stripping camera metadata all belong here. Each arrives when it works, and not as a menu entry before then.