As of 2016 there are 683 exits on Interstate 70 from Maryland to Utah. The number of exits per state ranges from 11 in Maryland to 134 in Colorado.
Interstate 70 has exits in 10 different states, with 35 exits in Maryland, 44 exits in Pennsylvania, 11 exits in West Virginia, 83 exits in Ohio and 41 exits in Indiana. The highway also has 42 exits in Illinois, 131 exits in Missouri, 131 exits in Kansas, 134 exits in Colorado and 31 exits in Utah.
The exit numbering system corresponds to mile markers of the highway in each state, which start at zero on each state's western border and move up heading east. For example, Indiana's 41 exits range from exit one in western Indiana near Terre Haute to exit 156 in eastern Indiana near Richmond.