Below you can see the front-view size comparison of the Olympus E-M10 II and Olympus E-M10 III. The Olympus E-M10 II is clearly the smaller of the two cameras. Its body is 2mm narrower, 1 mm shorter and 3 mm thinner than the Olympus E-M10 III.
The chart below depicts how two cameras compare with average dimensions of the cameras in their class.