Below you can see the front view size comparison of Olympus E-PL6 and Nikon 1 J3. Nikon 1 J3 is clearly the smaller of the two cameras. Its body is 10mm narrower, 3mm shorter and 9mm thinner than Olympus E-PL6.
Olympus E-PL6 vs Nikon 1 J3 - Front View
Olympus E-PL6 vs Nikon 1 J3 - Top View
The chart below depicts how two cameras compare with average dimensions of the cameras in their class.
Camera Size Comparison
Select Two Cameras for Size Comparison