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 Canon 700D and Canon 100D side-by-side from the front, back and top in their relative dimensions. Canon 700D has external dimensions of 133 x 100 x 79 mm (5.24 x 3.94 x 3.11″) and weighs 580 g (1.28 lb / 20.46 oz) (including batteries). Canon 100D has external dimensions of 117 x 91 x 69 mm (4.61 x 3.58 x 2.72″) and weighs 407 g (0.90 lb / 14.36 oz) (including batteries).
Below you can see the front-view size comparison of the Canon 700D and the Canon 100D. Canon 100D is clearly the smaller of the two cameras. Its body is 16mm narrower, 9mm shorter and 10mm thinner than Canon 700D.
Here is the back view size comparison of the Canon 700D and Canon 100D.
Now lets look at the top view comparison of Canon 700D and Canon 100D.
Weight is another important factor, especially when deciding on a camera that you want to carry with you all day.
Canon 100D is significantly lighter (173g ) than the Canon 700D which may become a big advantage especially on long walking trips.
Also keep in mind that body weight is not the only deciding factor when comparing two interchangeable camera bodies, you also have to take into account the lenses that you will be using with these bodies. Since both Canon 700D and Canon 100D have the same Canon EF/EF-S lens mount and APS-C sized sensors, lenses will not be a differentiator on total size of the system.
Weather Sealing
Unfortunately neither the Canon EOS 700D (EOS Rebel T5i) nor Canon EOS 100D (EOS Rebel SL1) 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 DSLR Cameras with Weather Sealing
LCD Screen Size and Features
Canon 700D and Canon 100D's LCD screens have the same diagonal size of 3.00 inches.
On the other hand, Canon 700D sports a
Fully Articulated screen which you can change the angle and position of the screen almost freely, making it possible to shoot from waist or over-the-head levels, and especially very useful for shooting selfies and video. Canon 100D's LCD screen is a fixed type which provides almost no flexibility in shooting positions compared to 700D.