If I can, I measure the person that will be using the lap quilt and let the person's height, as well as the intended use, dictate the final dimension of the individual quilt itself. I just finished my mother's own quilt. Since she is just under 5 foot, I made the quilt a square 45"x 45". She mostly sits up in her chair watch television with it. Although at times, she likes to lie down and cover herself with it.