Popular conversions
21 pairsMeter ↔ Kilometer
m ↔ km
Meter ↔ Centimeter
m ↔ cm
Meter ↔ Millimeter
m ↔ mm
Kilometer ↔ Mile
km ↔ mi
Meter ↔ Foot
m ↔ ft
Centimeter ↔ Millimeter
cm ↔ mm
Centimeter ↔ Inch
cm ↔ in
Meter ↔ Yard
m ↔ yd
Foot ↔ Inch
ft ↔ in
Mile ↔ Foot
mi ↔ ft
Micrometer ↔ Millimeter
µm ↔ mm
Nanometer ↔ Micrometer
nm ↔ µm
Nautical mile ↔ Kilometer
nmi ↔ km
Arshin ↔ Meter
arşın ↔ m
Arshin ↔ Centimeter
arşın ↔ cm
Endaze ↔ Meter
endaze ↔ m
Arshin ↔ Endaze
arşın ↔ endaze
Byzantine Foot ↔ Meter
pus ↔ m
Byzantine Foot ↔ Byzantine Fathom
pus ↔ orgyia
Cig ↔ Meter
çığ ↔ m
Cig ↔ Centimeter
çığ ↔ cm
Unit guides
16 units- What is Meter?m
- What is Kilometer?km
- What is Centimeter?cm
- What is Millimeter?mm
- What is Mile?mi
- What is Foot?ft
- What is Inch?in
- What is Yard?yd
- What is Micrometer?µm
- What is Nanometer?nm
- What is Nautical mile?nmi
- What is Arshin?arşın
- What is Endaze?endaze
- What is Byzantine Foot?pus
- What is Byzantine Fathom?orgyia
- What is Cig?çığ
Detailed guide to Length
Length is a physical quantity used to describe the distance between two points or the size of an object along a particular direction. It is one of the fundamental quantities used in science, engineering and everyday measurement.
The meter is the base unit of length in the International System of Units. Other metric length units are connected to the meter through decimal prefixes, while imperial and United States customary units use separately defined conversion relationships.
- Physical quantity
- Length
- SI base unit
- Meter
- SI symbol
- m
- Dimension symbol
- L
- Modern definition
- Distance traveled by light in vacuum during 1/299,792,458 of a second
What is length?
Length describes a one-dimensional extent. Depending on the direction being measured, it may represent distance, height, width, depth, thickness or diameter.
In dimensional analysis, length is represented by the symbol L. Many derived physical quantities, including area, volume, speed, acceleration and pressure, contain a length dimension.
The meter as the SI base unit
The meter is one of the seven base units of the International System of Units. It provides the reference from which metric length units and many derived units are constructed.
The modern meter is linked to the fixed value of the speed of light in vacuum. This makes the definition reproducible without depending on a physical measuring bar or a particular location on Earth.
Metric length units
Metric length units use prefixes that represent powers of ten. One kilometer equals 1,000 meters, one centimeter equals 0.01 meters and one millimeter equals 0.001 meters.
For extremely small measurements, units such as the micrometer and nanometer are used. Large geographical and road distances are commonly expressed in kilometers.
Imperial and US customary length units
The foot, mile, inch and yard are widely recognized non-metric length units. They are used primarily in the United States and in selected applications in the United Kingdom and other countries.
One international foot is exactly 0.3048 meters, while one international mile is exactly 1,609.344 meters. These exact definitions provide reliable conversion factors.
How are length units converted?
A length conversion changes the numerical value and unit while preserving the physical distance being represented. The original value is multiplied by the conversion factor between the two units.
Metric conversions often involve powers of ten. Conversions between metric and imperial systems require defined factors such as 2.54 centimeters per inch or 1,609.344 meters per mile.
Length measurement and uncertainty
Length may be measured using rulers, tape measures, calipers, micrometers, laser distance meters and optical instruments. The appropriate instrument depends on the size of the object and the required precision.
Every physical measurement has uncertainty. Instrument resolution, calibration, temperature, measurement technique and environmental conditions can all affect the reported value.
Length units
| Unit | Symbol | Information |
|---|---|---|
| Meter | m | View unit guide |
| Kilometer | km | View unit guide |
| Centimeter | cm | View unit guide |
| Millimeter | mm | View unit guide |
| Mile | mi | View unit guide |
| Foot | ft | View unit guide |
| Inch | in | View unit guide |
| Yard | yd | View unit guide |
| Micrometer | µm | View unit guide |
| Nanometer | nm | View unit guide |
| Nautical mile | nmi | View unit guide |
| Arshin | arşın | View unit guide |
| Endaze | endaze | View unit guide |
| Byzantine Foot | pus | View unit guide |
| Byzantine Fathom | orgyia | View unit guide |
| Cig | çığ | View unit guide |
Sources
The definitions and conversion relationships on this page are aligned with standard metrology and SI reference material.