Atomic absorption spectrophotometry analyzes the concentration of elements in a liquid sample based on energy absorbed from certain wavelengths of light (usually 190 to 900 nm). Atomic absorption spectrophotometers typically include a flame burner to atomize the sample (most commonly a hollow cathode lamp), a monochromator and a photon detector. Depending on the model, some atomic absorption spectrometers are equipped with a turret or fixed lamp socket that can hold multiple lamps (up to eight) to reduce downtime between samples or allow for sequential analysis.

Atomic absorption spectrometers are used in the pharmaceutical industry during drug development. In atomic absorption spectrometry, a sample is atomized, usually by a flame or graphite furnace, and dispersed into the light. A detector measures the amount of absorption in the sample and compares it to a reference with a known concentration of the element in question to determine its concentration in the sample. Some of the specifications to be aware of before purchasing an atomic absorption spectrometer are its wavelength range, what type of atomizer it uses, if it can do multiple tests for multiple elements, and if it has a single beam, double beam or both types of light source.

AAS is also used in food and beverage, water, and clinical analysis. It is also used in mining operations, such as to determine the percentage of precious metal in rocks.