Below you can see the front view size comparison of Sony A7R II and Nikon Z7. Sony A7R II is clearly the smaller of the two cameras. Its body is 7mm narrower, 5mm shorter and 8mm thinner than Nikon Z7.
Sony A7R II vs Nikon Z7 - Front View
Sony A7R II vs Nikon Z7 - Top View
The chart below depicts how two cameras compare with average dimensions of the cameras in their class.
Camera Size Comparison
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