# Length and distance conversions

length conversions
Select a unit of length

## What is length? What is distance?

Definition: Length is a physical property that expresses (quantitatively) how long something is; distance shows how far away something is. The base unit of length in the International System of Units (SI) is the metre (or meter, US spelling). Common units of length / distance currently in use include nanometers (nm), micrometers (µm), millimeters (mm), centimeters (cm), kilometers (km), miles (mi), inches (in), feet (ft), yards (yd) and light-years (ly).

## Common length conversions

• 1 meter = 100 centimeters = 1,000 millimeters
• 1 kilometer = 1,000 meters
• 1 mile = 1,609.344 meters = 5,280 feet
• 1 nautical mile = 1,852 meters = 1.852 kilometers
• 1 mile = 0.868976 nautical miles
• 1 foot = 0.3048 meters = 12 inches
• 1 yard = 0.9144 meters = 3 feet
• 1 inch = 2.54 centimeters = 0.0254 meters
• 1 angstrom = 10-10 meters = 0.1 nanometers
• 1 light-year = 0.306595 parsecs

## Subdivisions and multiples of the meter using SI prefixes

 Subdivisions of the meter Multiples of the meter Name Symbol Value Name Symbol Value decimeter dm 10-1 m decameter dam 101 m centimeter cm 10-2 m hectometer hm 102 m millimeter mm 10-3 m kilometer km 103 m micrometer μm 10-6 m megameter Mm 106 m nanometer nm 10-9 m gigameter Gm 109 m picometer pm 10-12 m terameter Tm 1012 m femtometer fm 10-15 m petameter Pm 1015 m attometer am 10-18 m exameter Em 1018 m zeptometer zm 10-21 m zettameter Zm 1021 m yoctometer ym 10-24 m yottameter Ym 1024 m