Zipper length?

Question

So I am making a dress, and I need to install a zipper. I have one that is 12 in and another that is 14 in, which one should I use, or should I get an entirely different one?

Answer 1

Whatever your preference or if using a pattern its whatever the pattern states.  Dont use too long a zip though or it with ruche up and look awful  xx

Answer 2

12 sounds good.