Furlong most practical measurements. Furlong A furlong is a measure of distance in imperial units and U.S. customary units equal to one eighth of a mile, equivalent to 660 feet, 220 yards, 40 rods, or 10 chains. Using the international definition of the inch as exactly 25.4 millimetres, one furlong is 201.168 metres. However, the United States does not uniformly use this conversion ratio. Older ratios are in use for surveying purposes in some states, leading to variations in the length of the furlong of two parts per million, or about 0.4 millimetres ( inch). This variation is too small to
Furlong United Kingdom, which define the furlong in terms of the international yard of exactly 0.9144 metres, a furlong is 201.168 m. Australia does not formally define the furlong, but it does define the chain and link in terms of the international yard. In the United States, which defines the furlong, chain, rod, and link in terms of the U.S. survey foot of exactly metre, a furlong is approximately 201.1684 m long. The United States does not formally define a "survey yard". The difference of approximately two parts per million between the U.S. value and the "international" value is insignificant for