Below you can see the front view size comparison of Nikon D5600 and Canon G12. Canon G12 is clearly the smaller of the two cameras. Its body is 12mm narrower, 21mm shorter and 22mm thinner than Nikon D5600.
Nikon D5600 vs Canon G12 - Front View
Nikon D5600 vs Canon G12 - Top View
The chart below depicts how two cameras compare with average dimensions of the cameras in their class.
Camera Size Comparison
Select Two Cameras for Size Comparison