In music, 53 equal temperament, called 53 TET, 53 EDO, or 53 ET, is the tempered scale derived by dividing the octave into 53 equal steps (equal frequency ratios). Each step represents a frequency ratio of 21⁄53, or 22.6415 cents , an interval sometimes called the Holdrian comma. 53-TET is a tuning of equal temperament in which the tempered perfect fifth is 701.89 cents wide, as shown in Figure 1. The interval of 7⁄4 is 4.8 cents sharp in 53-TET, and using it for 7-limit harmony means that the septimal kleisma, the interval 225⁄224, is also tempered out.