# Born rule

Calculation rule in quantum mechanics / From Wikipedia, the free encyclopedia

The **Born rule** (also called **Born's rule**) is a key postulate of quantum mechanics which gives the probability that a measurement of a quantum system will yield a given result.[1] In its simplest form, it states that the probability density of finding a particle at a given point, when measured, is proportional to the square of the magnitude of the particle's wavefunction at that point. It was formulated by German physicist Max Born in 1926.