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