Convert from em to U

Unit Definition (em)
The em is a printer's unit of relative distance. One em is the height of the type size (in points) being used. If 12 point type is being set, then one em is 12 points, and so on.

Unit Definition (U)
The U is a unit of distance used to measure the height of the standard racks in which audio, video, or computer components are mounted. 1U is equal to 1.75 inches (44.45 millimeters), so that, for example, a 2U component is 3.5 inches high, and a 22U rack houses a stack of components 38.5 inches high.