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 Panasonic GX8 and Nikon Z5 side-by-side from the front, back and top in their relative dimensions. Panasonic GX8 has external dimensions of 133 x 78 x 63 mm (5.24 x 3.07 x 2.48″) and weighs 487 g (1.07 lb / 17.18 oz) (including batteries). Nikon Z5 has external dimensions of 134 x 101 x 70 mm (5.28 x 3.98 x 2.76″) and weighs 675 g (1.49 lb / 23.81 oz) (including batteries).
Below you can see the front-view size comparison of the Panasonic GX8 and the Nikon Z5. Panasonic GX8 is clearly the smaller of the two cameras. Its body is 1mm narrower, 23mm shorter and 7mm thinner than Nikon Z5.
Here is the back view size comparison of the Panasonic GX8 and Nikon Z5.
Now lets look at the top view comparison of Panasonic GX8 and Nikon Z5.
Weight is another important factor, especially when deciding on a camera that you want to carry with you all day.
Panasonic GX8 is significantly lighter (188g ) than the Nikon Z5 which may become a big advantage especially on long walking trips.
Also keep in mind that body weight is not the only deciding factor when comparing two interchangeable camera bodies, you also have to take into account the lenses that you will be using with these bodies. Since Nikon Z5 has a Full frame sensor and Panasonic GX8 has a smaller Four Thirds sensor, Panasonic GX8's lenses for a similar focal length and aperture will generally be lighter and smaller than the Nikon Z5 lenses.
Weather Sealing
Both the GX8 and the Z5 have weather sealings in their bodies, making them resistant to water and dust.
LCD Screen Size and Features
Nikon Z5's 3.20" LCD screen is slightly larger than Panasonic GX8's 3" screen.