Size and weight is a big decision factor when you are trying to find the ideal camera for your needs.
In this section, We are going to illustrate Nikon L31 and Pentax I-10 side-by-side from the front, back and top in their relative dimensions. Nikon L31 has external dimensions of 96 x 59 x 29 mm (3.78 x 2.32 x 1.14″) and weighs 160 g (0.35 lb / 5.64 oz) (including batteries). Pentax I-10 has external dimensions of 101 x 65 x 28 mm (3.98 x 2.56 x 1.1″) and weighs 153 g (0.34 lb / 5.40 oz) (including batteries).
Below you can see the front view size comparison of Nikon L31 and Pentax I-10. Nikon L31 is 5mm narrower and 6mm shorter than Pentax I-10 but it is also 1mm thicker.
Here is the back view size comparison of Nikon L31 and Pentax I-10.
Now lets look at the top view comparison of Nikon L31 and Pentax I-10.
Weight is another important factor especially when deciding on a camera that you want to carry with you all day.
Pentax I-10 is 7g lighter than the Nikon L31 but we don't think this will make a significant difference.
Unfortunately neither Nikon Coolpix L31 nor Pentax Optio I-10 provides any type of weather sealing in their body, 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
Nikon L31 and Pentax I-10's LCD screens has the same diagonal size of 2.70".
Unfortunately, both cameras has fixed screens so they don't tilt or flip in directions.