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 Canon 7D 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). Canon 7D has external dimensions of 148 x 111 x 74 mm (5.83 x 4.37 x 2.91″) and weighs 860 g (1.90 lb / 30.34 oz) (including batteries).
Below you can see the front view size comparison of Nikon L31 and Canon 7D. Nikon L31 is clearly the smaller of the two cameras. Its body is 52mm narrower, 52mm shorter and 45mm thinner than Canon 7D. As you can tell, actually this is not a fair size comparison since Nikon L31 has a built-in lens but Canon 7D doesn't. Once you put a lens on 7D, its thickness will increase significantly.
Here is the back view size comparison of Nikon L31 and Canon 7D.
Weight is another important factor especially when deciding on a camera that you want to carry with you all day.
Nikon L31 is significantly lighter (700g ) than the Canon 7D which may become a big advantage especially on long walking trips.
Again, this comparison may not be very useful in real life as we are comparing the weight of a camera with a built-in lens to the body-only weight of an interchangeable lens camera. Once you put a lens on 7D, the total kit will weigh much higher.
Thanks to the weather sealed body of 7D, you can use this camera with more confidence under conditions where there is risk of exposure to water and dust compared to L31.
LCD Screen Size and Features
Canon 7D's 3" LCD screen is slightly larger than Nikon L31's 2.7" screen.
Unfortunately, both cameras has fixed screens so they don't tilt or flip in directions.