I made a duvet cover out of a jelly roll and 10" squares. I did wash the fabric before I used it and ended up with 8 1/2" usuable squares. I had to go down to the smallest usable size, they all didn't shrink that much. The jelly roll strips didn't shrink as much, but they frayed to beat a band. I don't think I will buy their precuts again, but it was a good experience and my son enjoyed the cover!