Meters to Nanometers (m to nm)

1 meter equals 1,000,000,000 nanometers exactly.

1 meter = 1,000,000,000 nanometers

How to convert meters to nanometers

To convert meters to nanometers, multiply the number of meters by 1,000,000,000. This factor is exact. To go the other way, multiply nanometers by 1×10⁻⁹.

nanometers = meters × 1,000,000,000

Example: 10 meters = 10,000,000,000 nanometers.

About these units

Meter (m)

Metric (SI)Current unit

The SI base unit of length. Since 1983 it is defined as the distance light travels in a vacuum in 1/299,792,458 of a second.

Meter comes from the Greek metron, a measure. In 1791 the French National Assembly defined it as one ten-millionth of the distance from the equator to the North Pole along a great circle through Paris, after rejecting the length of a seconds pendulum because that length changes with local gravity. The surveyors Delambre and Méchain measured the meridian arc, and in 1799 a platinum bar known as the Mètre des Archives became the physical standard. NIST notes that this Earth-based meter turned out to be about 0.2 mm shorter than the true pole-to-equator fraction it was meant to represent.

The 1875 Treaty of the Meter created the CGPM and the BIPM to look after common standards, and in 1889 a platinum-iridium prototype bar took over; the original is still kept at the BIPM. In 1960 the meter was tied to 1,650,763.73 wavelengths of an orange-red krypton-86 line, and in 1983 to the speed of light, which made length a quantity derived from the time standard. The 2018 revision reworded that definition without changing the meter's size. NIST offers a handy yardstick for scale: a pace, meaning two steps, is roughly a meter or a yard.

The meter is the reference unit for length on this site.

Sources: BIPM: history of the metre; NIST: the meter and the SI redefinition; Wikipedia: Metre

Nanometer (nm)

Metric (SI)Current unit

One billionth of a meter. Used for the wavelength of light (visible light is about 400–700 nm) and for chip feature sizes.

Greek for dwarf gave nano- its name, and the nanometer was once called something clumsier: the millimicrometre, or more often the millimicron, written mμ, since it is a thousandth of a micrometer. The prefix nano- was among those officially adopted when SI prefixes were first introduced in 1960, and the nanometer grew into the standard unit for optics and microelectronics. It sits a factor of ten above the older ångström, which is 0.1 nm and is still used for atomic distances.

Visible light spans roughly 400 to 700 nm, which is why color and spectroscopy are quoted this way. A helium atom is about 0.06 nm across and a ribosome about 20 nm. Chip makers have used nanometers since the late 1980s in names for manufacturing generations such as 32 nm and 22 nm. Those are labels for successive generations in the industry roadmap, and they describe typical feature sizes rather than one exact measurement. Readers should also beware that nm is sometimes written informally for the nautical mile.

1 nanometer = 1×10⁻⁹ meters (exactly).

Sources: Wikipedia: Nanometre; Wikipedia: Metric prefix; Wikipedia: Nautical mile

Related conversions

See all length units.