Below you can see the front view size comparison of Canon 1D MII and Sony A9. Sony A9 is clearly the smaller of the two cameras. Its body is 29mm narrower, 62mm shorter and 17mm thinner than Canon 1D MII.
Canon 1D MII vs Sony A9 - Front 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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