Size and weight are big decision factors when you are trying to find the ideal camera for your needs.
In this section, we are going to illustrate the Olympus VG-120 and Nikon 1 J3 side-by-side from the front, back and top in their relative dimensions. Olympus VG-120 has external dimensions of 96 x 57 x 19 mm (3.78 x 2.24 x 0.75″) and weighs 120 g (0.26 lb / 4.23 oz) (including batteries). Nikon 1 J3 has external dimensions of 101 x 61 x 29 mm (3.98 x 2.4 x 1.14″) and weighs 201 g (0.44 lb / 7.09 oz) (including batteries).
Below you can see the front-view size comparison of the Olympus VG-120 and the Nikon 1 J3. Olympus VG-120 is clearly the smaller of the two cameras. Its body is 5mm narrower, 4mm shorter and 10mm thinner than Nikon 1 J3. As you can tell, actually this is not a fair size comparison since Olympus VG-120 has a built-in lens but Nikon 1 J3 doesn't. Once you put a lens on 1 J3, its thickness will increase significantly.
Now lets look at the top view comparison of Olympus VG-120 and Nikon 1 J3.
Weight is another important factor, especially when deciding on a camera that you want to carry with you all day.
Olympus VG-120 is significantly lighter (81g ) than the Nikon 1 J3 which may become a big advantage especially on long walking trips.
Again, this comparison may not be very useful in real life as we are comparing the weight of a camera with a built-in lens to the body-only weight of an interchangeable lens camera. Once you put a lens on 1 J3, the total kit will weigh much higher.
Weather Sealing
Unfortunately neither the Olympus VG-120 nor Nikon 1 J3 provides any type of weather sealing in their bodies, so you have to give extra care especially when you are shooting outdoors. If weather sealing is a must-have feature for you, check these sections: Top Compact Cameras with Weather Sealing Top Mirrorless Cameras with Weather Sealing
LCD Screen Size and Features
Olympus VG-120 and Nikon 1 J3's LCD screens have the same diagonal size of 3.00 inches.
Unfortunately, both cameras has fixed screens so they don't tilt or flip in directions.