Ask the MB: Sideburn Length to Width Ratio
A: When it comes to sideburn length, follow the golden ratio — 1.6180339887. In other words, if you want sideburns 1 inch in width, make sure they are 1.6180339887 inches long. We know maintaining that degree of precision sounds tough, but over time, you will master it.
Throughout history, Wikipedia tells us, architects, artists, industrial designers, and Mother Nature herself have relied on the golden ratio as an aesthetic guide. If it's good enough for da Vinci, Mondrian, Le Corbusier, and the Parthenon, it's good enough for your face.
Use the chart below as a handy guide.