Auger electron spectroscopy is widely used for quantitative analysis of adsorbed layers. In this paper, we derive a simple equation for the adsorption coverage by one type of atom or simple molecules. We also extend the discussion to the case in which two different species are adsorbed, one on top of the other, and arrive at a system of two linear equations, from which the coverage of each layer can easily be derived. In both cases, data from only one Auger spectrum are sufficient in order to determine the coverage. The analysis is applied to the case of simultaneous hydrocarbon and oxygen adsorption on silver. The coverage so determined agrees very well with that derived from measurements of adsorption as a function of exposure.