How
are cigars measured? Ring gauge, or the diameter of a cigar, is measured in
64ths of an inch. So for example, a cigar that has a ring gauge of 42 is in
fact 42/64ths of an inch in diameter. In some countries, diameter is expressed
in millimeters. Length is expressed in different units depending on where in
the world you are buying a cigar. In the U.S., length is given in inches. In
many other countries, length is expressed in centimeters.