21x21 has an aspect ratio of 1:1. A typical 21x21 frame will cover 1/4 inch of your image all around, resulting in a view window of 20.5x20.5. If you would like a mat to complement your frame, visit our 21x21 Cut Mats. With a mat, a 21x21 frame works best for artwork from 10x10 to 17x17.
Learn more about measuring for a frame