Convert Meter to Nanometer

The meter is the SI base unit of length. Since 2019, the meter has been defined by fixing the numerical value of the speed of light in vacuum to exactly 299,792,458 meters per second. Every other SI length unit derives from the meter.

The meter was originally defined in 1793 by the French Academy of Sciences as one ten-millionth of the distance from the equator to the North Pole along a meridian through Paris. It has been redefined multiple times — by physical prototype, then by atomic transitions, and finally in 2019 by fundamental physical constants.

The meter is the international standard for length in science, engineering, construction, athletics, and everyday measurement in metric countries. It underpins definitions of area (m²), volume (m³), and most derived SI units.

Established 1793 in France; ratified internationally via the Metre Convention 1875; redefined in 1960, 1983, and most recently 2019 when the SI redefinition fixed it to the speed of light.

A nanometer is a metric unit of length equal to one billionth of a meter (1×10⁻⁹ m). It is the standard unit for measuring atomic and molecular dimensions and is widely used in physics, chemistry, and electronics.

Defined using the SI prefix nano- (from Greek nanos, "dwarf") to denote one-billionth, adopted by the General Conference on Weights and Measures (CGPM) in 1960.

Nanometers are used to measure wavelengths of visible light (400–700 nm), semiconductor transistor sizes (currently 3–5 nm process nodes), DNA double helix width (2 nm), and atomic radii. The 2019 SI redefinition fixed the meter to the speed of light, making nanometer definitions exact to atomic precision.

SI prefix nano- adopted by the CGPM in 1960; nanometer became the standard unit for nanotechnology and optical wavelengths during the late 20th century.