The short answer: how high to hang a mirror depends on whether there is furniture underneath. On a blank wall, centre it at eye level, 57 to 65 inches from the floor. Above furniture, measure from the furniture instead and leave a gap of 4 to 8 inches, closing that gap as the furniture gets taller: 8 to 12 inches above a low dresser, 6 to 8 above a standard one, and only 3 to 5 above anything over 40 inches. Then check the third thing, which almost nobody mentions: stand where you will normally stand and look at what the mirror will actually reflect. A mirror hung at a technically perfect height that reflects a blank ceiling or a doorway into the bathroom is a mirror in the wrong place.
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