Conversion Factors for Units of Length
1 inch = 2.54 centimeters
1 foot = 0.305 meter
1 yard = 0.914 meter
1 mile = 1.609 kilometers
1 nautical mile = 1.852 kilometers
1 centimeter = 0.39 inch
1 meter = 39.37 inches = 3.28 feet = 1.094 yards
1 kilometer = 0.62 mil
American and British Units of Length
1 inch (in.) = 1/36 yard = 1/12 foot
1 foot (ft) = 1/3 yard
1 yard (yd; basic unit of length
1 rod (rd) = 5 1/2 yards
1 furlong (fur.) = 220 yards = 1/8 mile
1 mile (mi) = 1,760 yards = 5,280 feet
1 fathom (fath) = 6 feet
1 nautical mile = 6,076.1 feet
Metric Units of Length
1 millimeter (mm) = 1/1,000 meter
1 centimeter (cm) = 1/100 meter
1 decimeter (dm) = 1/10 meter
1 meter (m; basic unit of length)
1 dekameter (dkm) = 10 meters
1 kilometer (km) = 1000 meters
1 Amstrom = 10-10 meters
Since the Mendenhall Order of 1893,
the U.S. yard and pound and all units derived from them
have been defined in terms of the metric units of length and mass,
the meter (m) and the kilogram (kg);
since 1959 these values are 1 yd = 0.9144 m and 1 lb = 0.45359237 kg.
In the United States, the older definition
of the yard as 3,600/3,937 m
is still used for surveying, the corresponding foot (1,200/3,937 m) being
known as the survey foot.