Below you can see the front-view size comparison of the Fujifilm XQ1 and Olympus E-PL8. The Fujifilm XQ1 is clearly the smaller of the two cameras. Its body is 15mm narrower, 8 mm shorter and 5 mm thinner than the Olympus E-PL8.
The chart below depicts how two cameras compare with average dimensions of the cameras in their class.