Quantization of charge is a property of electric charge, which means that the charge can only exist in nature in the form of an integral multiple of the charge on one electron or proton. In other words, any charged particle can have a charge equal to some integral number of e, where e is the charge on an electron, i.e., Q = ne, where n=1, 2, 3, … . This property was first suggested by the experimental laws of electrolysis by Faraday and was experimentally demonstrated by Millikan in 1912. The main reason for quantization is that when two bodies are rubbed, only an integer number of electrons are transferred from one body to another.

The quantization of charge is a fundamental concept in physics and is related to the conservation of charge. All free charges are integral multiples of a basic unit charge “e” . The total charge of an isolated system is always conserved. The quantization of charge is generally ignored at macroscopic levels because at that point, charges are considered to be continuous.