Convert Kilometer (km) to Nanometer (nm) instantly.
About these units
Kilometer (km)
A kilometer is equal to one thousand meters and serves as the standard large-scale terrestrial distance unit in nearly all countries that use the metric system. It provides a convenient middle ground between the human walking scale and the geographic scale of cities, regions, and countries. Road signs, maps, geographic information systems, and national transportation networks rely heavily on kilometers to express distances succinctly and uniformly. Because kilometers integrate seamlessly into the metric system, they also appear in scientific contexts—ranging from geologic fault lengths to atmospheric layer thicknesses. In natural disasters such as earthquakes or volcanic eruptions, distances from epicenters or vents are often measured in kilometers to communicate scale effectively to the public. The kilometer's widespread use demonstrates the power of the metric system's decimal structure, offering simplicity and international standardization.
Nanometer (nm)
A nanometer—one billionth of a meter (10⁻⁹ m)—is central to nanoscience, nanotechnology, and molecular biology. Many structures essential to life fall into this scale: DNA's double helix is about 2 nm wide, viruses often measure tens to hundreds of nanometers, and key cell structures like ribosomes are on the order of 20–30 nm. In engineering, nanometers define the dimensions of modern semiconductor technology. Silicon transistors have shrunk to features only a few nanometers wide, approaching the physical limits of electron behavior in solid-state materials. In optics, wavelengths of ultraviolet light can be expressed in nanometers, as can surface roughness, material grain sizes, and thin-film coatings. The nanometer is ubiquitous across modern science because it describes both biological and technological structures at the frontier of research.