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 Casio EX-Z450 and Nikon S5100 side-by-side from the front, back and top in their relative dimensions. Casio EX-Z450 has external dimensions of 81 x 56 x 21 mm (3.19 x 2.2 x 0.83″) and weighs 128 g (0.28 lb / 4.52 oz) (including batteries). Nikon S5100 has external dimensions of 97 x 57 x 22 mm (3.82 x 2.24 x 0.87″) and weighs 132 g (0.29 lb / 4.66 oz) (including batteries).
Below you can see the front-view size comparison of the Casio EX-Z450 and the Nikon S5100. Casio EX-Z450 is clearly the smaller of the two cameras. Its body is 16mm narrower, 1mm shorter and 1mm thinner than Nikon S5100.
Here is the back view size comparison of the Casio EX-Z450 and Nikon S5100.
Weight is another important factor, especially when deciding on a camera that you want to carry with you all day.
Casio EX-Z450 is 4g lighter than the Nikon S5100 but we don't think this will make a significant difference.
Weather Sealing
Unfortunately neither the Casio Exilim EX-Z450 nor Nikon Coolpix S5100 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
LCD Screen Size and Features
Casio EX-Z450's 3.00" LCD screen is slightly larger than Nikon S5100's 2.7 screen.
Unfortunately, both cameras has fixed screens so they don't tilt or flip in directions.