The ring sizer will enable you to find out the size of any ring, so that you can find out your own finger size, or that of the person to whom you want to give a gift. We have created a PDF document that you just have to print out to its full size. To do this, you need to make sure that the length of the marked-out line is exactly 3.9 inches. Then all you have to do is place your ring on the different circles until you find the right one. The right fit will be the one where you can view the circle inside your ring but without there being any clear space between the circle and the ring. There is very little difference between 2 neighboring ring sizes, sizes 52 and 53 being virtually identical, for example. Your finger can accomodate a size difference of 1mm either way.