Tire sizes can appear to be confusing at first, however after understanding them they can actually be quite simple.
There are three different styles of tire sizes. One style uses a dash between two numbers, the other style uses a forward slash and a dash between three numbers, and the other style use an X between two numbers. Here are examples of these three styles:
Style 1: 3.00-10
Style 2: 3.00/3.50-10
Style 3: 16X3.0
Style 1 tires: The number before the dash (-) is the tire section height and tire width, which are the same. The number after the dash is the rim diameter.
Style 2 tires: The number before the forward slash (/) is the tire section height. The number after the forward slash (/) is the tire width. And the number after the dash (-) is the rim diameter.
Style 3 tires: The number before the X is the overall tire diameter. The number after the X is the tire width.