FABRICS > Precut Sizes > Fat Quarter / 18" x 20" The good old stand by cut of fabric that we just can't live without. When you just have to have a piece of that or you won't be able to sleep grab a fat quarter and feel the satisfaction of completeness. A fat quarter is a half of a yard that is split in half along the fold to yield a 18" x 20" chunk of fabric. There are thousands of patterns designed for fat quarters. Don't forget to buy some matching yardage for borders and binding.