Here is a side by side comparison of the Canon EOS R vs Nikon Z7 vs Sony A7 III full frame mirrorless cameras.
Check out the images below comparing the Canon EOS R to both the Sony A7 III and Nikon Z7. Sony looks to be the smallest of these three models, with the Canon and Nikon being closer in size, but the Canon a slightly larger grip and overall thickness.
Fotohanskeuzekamp.nl has shared these side by side images of the Canon EOS R vs Nikon Z7 vs Sony A7 III. Check out the availablity of the Canon EOS R in stock, Nikon Z7 in stock and Sony A7 III.