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 Fujifilm XQ2 and Pentax K-01 side-by-side from the front, back and top in their relative dimensions. Fujifilm XQ2 has external dimensions of 100 x 59 x 33 mm (3.94 x 2.32 x 1.3″) and weighs 206 g (0.45 lb / 7.27 oz) (including batteries). Pentax K-01 has external dimensions of 122 x 79 x 58 mm (4.8 x 3.11 x 2.28″) and weighs 561 g (1.24 lb / 19.79 oz) (including batteries).
Below you can see the front-view size comparison of the Fujifilm XQ2 and the Pentax K-01. Fujifilm XQ2 is clearly the smaller of the two cameras. Its body is 22mm narrower, 20mm shorter and 25mm thinner than Pentax K-01. As you can tell, actually this is not a fair size comparison since Fujifilm XQ2 has a built-in lens but Pentax K-01 doesn't. Once you put a lens on K-01, its thickness will increase significantly.
Now lets look at the top view comparison of Fujifilm XQ2 and Pentax K-01.
Weight is another important factor, especially when deciding on a camera that you want to carry with you all day.
Fujifilm XQ2 is significantly lighter (355g ) than the Pentax K-01 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 K-01, the total kit will weigh much higher.
Weather Sealing
Unfortunately neither the Fujifilm XQ2 nor Pentax K-01 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
Fujifilm XQ2 and Pentax K-01'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.