Five kilometers is equal to three miles and 188.07 yards. In road races, five kilometers is usually just referred to 3.1 miles. One kilometer equals 0.6214 miles and one mile equals 1.6093 kilometers.
Kilometers are part of the metric system, also known as the International System of Units or the abbreviation SI. This internationally recognized and adopted system works on decimals, and one kilometer equals 1000 meters. The United States is the only industrialized nation that has not adopted the metric system as its official system. Although the metric system is approved and taught in the United States, the U.S. customary units are much more prevalent.