My knitting bag is 11" wide and 13" deep. It closes with this kind of string system that you pull from 2 sides of the bag and the bag closes (I think it might be called double loop). I knit mainly small things as well and this size has proved perfect since the knitting needles I use are either dpn or about 10" long. I have used this bag for over 3 years and couldnīt wish for a better one since it is big enough to carry sometimes up to 3 projects and yet small enough to take with me anywhere I go
I made a knitting bag for my friend and hers is 12" wide and 15" tall because the knitting needles she uses are 13".
--anu