Nikon S3100 weighs 118 g (0.26 lb / 4.16 oz) and has external dimensions of 94 x 58 x 18 mm (3.7 x 2.28 x 0.71″). Considering that the average weight of Compact type cameras is 188g, Nikon S3100 is a remarkably light camera for its class. Even better, with a thickness of only 18mm, it is also quite small, 10mm thinner than the average of its class.
Here is the front and top view image of Nikon S3100 with the dimensions:
In order to give you a better idea about the real life size of Nikon S3100, we have added an image of how it looks next to a credit card and an AA type battery.
Now lets compare the weight and thickness of Nikon S3100 with its main competitors:
Nikon S3100 doesn't have any environmental sealings on its body so you got to be extra careful to protect it against water and dust. If you shoot under these conditions very often, consider checking Top Compact Cameras with Weather Sealing page.