# Plank length conversions

The Plank length conversion selector above selects the length/distance measurement unit to convert to starting from Plank lengths. To make a conversion starting from a unit of length other than Plank length, simply click on the "Reset" button.

## About Plank length

The **Plank length** is the base unit of length in the system of Plank units equal to 1.6162 × 10^{-35} meters (1 Plank length = 1.616252 × 10^{-35} m), the base unit of length in the International System of Units (SI).

The Plank length is also equal to 1.616252 × 10^{-25} angstroms (Å) (a non-SI unit of length), or 1.616252 × 10^{-26} nanometers (nm), or 1.616252 × 10^{-29} micrometers (μm) or 1.616252 × 10^{-32} millimeters (mm), which are SI units of length.

The Planck units (or natural units) are units of measurement defined exclusively in terms of the following five universal physics constants: Gravitational constant (G), reduced Planck constant (h), Speed of light in a vacuum (c), Coulomb constant (ke or k), and Boltzmann constant (kB). In the Plank units, all these constants are normalized to 1. Thus, unlike the other measurement units, the Plank units are not based on the properties of any prototype object or particle but only on the properties of free space.

The Plank units are used in quantum physics.

Plural: Plank lengths