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 Nikon S3100 and Sony TX66 side-by-side from the front, back and top in their relative dimensions. Nikon S3100 has external dimensions of 94 x 58 x 18 mm (3.7 x 2.28 x 0.71″) and weighs 118 g (0.26 lb / 4.16 oz) (including batteries). Sony TX66 has external dimensions of 93 x 54 x 13 mm (3.66 x 2.13 x 0.51″) and weighs 109 g (0.24 lb / 3.84 oz) (including batteries).
Below you can see the front-view size comparison of the Nikon S3100 and the Sony TX66. Sony TX66 is clearly the smaller of the two cameras. Its body is 1mm narrower, 4mm shorter and 5mm thinner than Nikon S3100.
Here is the back view size comparison of the Nikon S3100 and Sony TX66.
Now lets look at the top view comparison of Nikon S3100 and Sony TX66.
Weight is another important factor, especially when deciding on a camera that you want to carry with you all day.
Sony TX66 is 9g lighter than the Nikon S3100 but we don't think this will make a significant difference.
Weather Sealing
Unfortunately neither the Nikon Coolpix S3100 nor Sony Cyber-shot DSC-TX66 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
Sony TX66's 3.30" LCD screen is slightly larger than Nikon S3100's 2.7" screen.
Unfortunately, both cameras has fixed screens so they don't tilt or flip in directions.