No, its not your imagination. It is not a rectangle. Some how I made it get wider as I went along. The beginning was 34 inches wide. The end is 41 inches. It is 30 inches long. I am thinking about crocheting around all 4 sides now. Maybe that might help it. I'm also thinking about washing it when I'm done to help block it, and to tighten up the stitches. Either way, its for the floor in my laundry room, so it does not need to be perfect.