Size and Weight Comparison
Size of a lens is an important deciding factor when comparing two lenses.Canon 18-55mm f3.5-5.6 is the longer of the two lenses at 80mm. The Canon 18-55mm f3.5-5.6 IS STM with a length of 75mm is 5mm shorter. On the other hand, there is no difference between the max diameters of these lenses, both coming at 69mm.
Weight of a lens is as important as its external dimensions, especially if you are planning to hand hold your camera and lens combination for longer periods. Canon 18-55mm f3.5-5.6 weighs 190g, which means it is 15g (7%) lighter than the Canon 18-55mm f3.5-5.6 IS STM which has a weight of 205g.
Below you can find the dimension and weight table of the 'Standard Zoom Lenses in Canon EF-S Mount for size comparison purposes.
Standard Zoom Lenses in Canon EF-S Mount for Size Comparison
Both Canon 18-55mm f3.5-5.6 and Canon 18-55mm f3.5-5.6 IS STM has the same Canon EF-S lens mount. Some of the latest released cameras that are compatible with the Canon EF-S lenses are Canon T8i, Canon 90D and Canon SL3.
Both lenses have the same focal range of 18-55mm and the fastest aperture of F3.5 - F5.6.