Length unit conversion is a way of length conversion. The unit of length refers to the basic unit for measuring the distance in space, and is the basic unit of measurement formulated by humans in order to standardize the length.

Commonly used units are millimeters (mm), centimeters (cm), decimeters (dm), kilometers (km), meters (m), micrometers (μm), nanometers (nm) and so on.

### International standard unit of length

In the International System of Units, the standard unit of length is "meter", which is represented by the symbol "m". These length units are all metric units.

### Imperial length unit

A few European and American countries, dominated by the United Kingdom and the United States, use imperial units, so the length units they use are different, mainly in miles, yards, feet, and inches.

Mile (mile) 1 mile = 1760 yards = 5280 feet = 1.609344 kilometers
Yard (yard, yd) 1 yard = 3 feet = 0.9144 meters
Fathom (f, fath, Fa, ftm) 1 fathom = 2 yards = 1.8288 meters
1 furlong = 220 yards = 201.17 meters
Feet (foot, ft, plural feet), 1 foot = 12 inches = 30.48 cm
Inch (inch, in), 1 inch = 2.54 cm

### Astronomical Length Unit

In astronomy, "light-year" is often used as a unit of length. It is the distance traveled by light in one year in a vacuum, so it is called light-year.

1 light-year=9.4653×10^12km
1 parsec = 3.2616 light years
1 astronomical unit ≈ 149.6 million kilometers

### Other length units include

Pami (Pm), megameters (Mm), kilometers (kilometers) (km), decimeters (dm), centimeters (cm), millimeters (mm), silk meters (dmm), hue meters (cmm), micrometers (μm), nanometer (nm), picometer (pm), femtometer (fm), ammeter (am), etc. Their conversion relationship with meters is as follows:

1PM(Pami)=1×10^15m
1Mm(Megameter)=1×10^6m
1km(Kilometer)=1×10^3m
1dm(Decimeter)=1×10^(-1)m
1cm(Centimeter)=1×10^(-2)m
1mm(Millimeter)=1×10^(-3)m
1μm(Micron)=1×10^(-6)m
1nm(Nano)=1×10^(-9)m
1pm(Pimi)=1×10^(-12)m
1fm(Fermi)=1×10^(-15)m
1am(Attometer)=1×10^(-18)m