Nano (symbol n) is a unit prefix meaning one billionth. Used primarily with the metric system, this prefix denotes a factor of 10−9 or 0.000000001. It is frequently encountered in science and electronics for prefixing units of time and length.

The prefix derives from the Greek νᾶνος (Latin nanus), meaning "dwarf". The General Conference on Weights and Measures (CGPM) officially endorsed the usage of nano as a standard prefix in 1960.

When used as a prefix for something other than a unit of measure (as for example in words like "nanoscience"), nano refers to nanotechnology, or means "on a scale of nanometres" (nanoscale).

Nanometre (Nanometer)

Different lengths as in respect to the electromagnetic spectrum, measured by the metre and its derived scales. The nanometre is often used to express dimensions on an atomic scale and mostly in the molecular scale.

The nanometre (international spelling as used by the International Bureau of Weights and Measures; SI symbol: nm), or nanometer (American spelling), is a unit of length in the International System of Units (SI), equal to one billionth (short scale) or one thousand millionth (long scale) of a metre (0.000000001m) and to 1000picometres. One nanometre can be expressed in scientific notation as 1 × 10−9m and as ⁠1/1000000000⁠m.

X-rays have a wavelength ranging from the size of 0.01 nm to 10 nm.

Three gold atoms lined up are about one nanometer (nm) long.

Human fingernails grow at approximately one nanometer per second.

Nanosecond

A nanosecond (ns) is a unit of time in the International System of Units (SI) equal to one billionth of a second, that is, ⁠1/1000000000⁠ of a second, or 10−9 seconds.

The term combines the SI prefix nano- indicating a 1 billionth submultiple of an SI unit (e.g. nanogram, nanometre, etc.) and second, the primary unit of time in the SI.

A nanosecond is to one second, as one second is to approximately 31.69 years.

A nanosecond is equal to 1000picoseconds or ⁠1/1000⁠microsecond. Time units ranging between 10−8 and 10−7 seconds are typically expressed as tens or hundreds of nanoseconds.

Time units of this granularity are commonly found in telecommunications, pulsed lasers, and related aspects of electronics.

One nanosecond (ns) is about the time required for light to travel 30 cm in air, or 20 cm in an optical fiber.

See also

SI prefixesvte
PrefixBase 10DecimalAdoption
NameSymbol
quettaQ103010000000000000000000000000000002022
ronnaR10271000000000000000000000000000
yottaY102410000000000000000000000001991
zettaZ10211000000000000000000000
exaE101810000000000000000001975
petaP10151000000000000000
teraT101210000000000001960
gigaG1091000000000
megaM10610000001873
kilok10310001795
hectoh102100
decada10110
1001
decid10−10.11795
centic10−20.01
millim10−30.001
microμ10−60.0000011873
nanon10−90.0000000011960
picop10−120.000000000001
femtof10−150.0000000000000011964
attoa10−180.000000000000000001
zeptoz10−210.0000000000000000000011991
yoctoy10−240.000000000000000000000001
rontor10−270.0000000000000000000000000012022
quectoq10−300.000000000000000000000000000001
Notes