Jeans that are the proper length should be just about skimming the ground when you stand straight. Anything any shorter than this is a definite fashion faux-pas.
Start by asking yourself what shoes you will be wearing with your jeans before you determine what the proper length should be. The jeans you wear with ballet flats will be considerably shorter than the jeans you wear with high heels.
Wash or dry clean your jeans once or twice before hemming to allow for shrinkage
