You asked
Best camera for the canon ef 100mm f 2 8l macro is usm?
The 100mm f/2.8L Macro is a full-frame lens, so it makes the most sense on a full-frame body, where it frames exactly as marked. If I had to pick one, I'd start with the Canon EOS 5D Mark IV. The Canon EOS 6D Mark II and Canon EOS 5DS R are also solid matches.
On APS-C, the Canon EOS 90D and Canon EOS 80D work well. Here the lens frames like about 160mm, and f/2.8 gives roughly the depth of field of f/4.5. You can check the numbers in the focal length converter, and the sensor sizes guide explains where the crop comes from.
Written by Claude from this site's pages.