Size is relative; therefore, six inches can be small or large when compared to other lengths. Six inches is very close to, but slightly shorter than, the length of a dollar bill.
For a frame of reference to understand how long six inches is, the length of a dollar bill is 6.14 inches. Six inches is relatively small compared to the length of a ruler, as the length of a standard ruler is 12 inches. However, six inches is relatively large when compared to the diameter of a quarter, which is just 0.955 inches across.
Six inches is quite small when compared to the height of a person. For example, in the United States, the average height of an adult male is 5 feet 9.5 inches, or 69.5 inches. Therefore, six inches is just under 1/10 the height of the average adult male in the United States.