>>3846460You can compare sizes (including with lenses) on
camerasize.com.
FP's the smallest, but it sucks if what you're wanting is a stills camera. It's really designed for video, not still photography, and it shows.
The A7 line and the RP are about the same size. I personally hate the interface/controls on the A7II (and by extension, probably the A7), but I've never tried an A7III and it might not suck so much. I've also never tried an EOS RP, but I have a hell of a lot more faith in Canon to design a usable camera than I do Sony based on all of the camera gear I've used.
The size difference between all of the mirrorless FF bodies (even between the worlds-smallest FP and the biggest ones like the A1 and Nikon Z7) is pretty negligible based on the numbers, and even more so based on actual usage, so I'd really recommend getting one that's got good usability rather than trying to shave a couple of millimeters off of your kit.
