Dining rooms come in all shapes, sizes, and configurations, so it's best not to pick a rug based on the sheer size of your dining room. Rather, finding the right size area rug is mostly dependent on the size of your table. An area rug too big for your table can swallow the furniture, or even make it look like a carpet rather than a rug. An area rug too small can make it nonfunctional, pulling your chairs in and out on the rug would be a hassle and the rug may not be under certain people's feet when sitting.