What thickness are guitar strings?
Essentially, the thickness of each string is measured in inches. In a set of 9s, the thinnest ‘E’ string is 0.009 of an inch, and in a set of 10s, you guessed it, the thin ‘E’ is 0.010 of an inch. A typical set of 9s will run from a 0.009 string, to a 0.042 string (9, 11, 16, 24, 32 42).