Jeans should be comfortably tight at first. If the jeans your trying on are really uncomfortably tight then they will probably only stretch a few inches. The best way to see if the jeans are going to be good for you is to do the sitting test. Sit down as you would in a car, and see how it feels. It's a good idea to wear new jeans around the house for approx an hour to see if the denim gives. Be sure to keep the tags on in case you need to return them.