Mass spectrometry is an analytical tool useful for measuring the mass-to-charge ratio (m/z) of one or more molecules present in a sample. These measurements can often be used to calculate the exact molecular weight of the sample components as well.

A mass spectrum will usually be presented as a vertical bar graph, in which each bar represents an ion having a specific mass-to-charge ratio (m/z) and the length of the bar indicates the relative abundance of the ion. The most intense ion is assigned an abundance of 100, and it is referred to as the base peak.

In a mass spectrometry experiment, the process sequence of analysis works in five stages, including sample introduction, analyte ionization, mass analysis, ion detection, and data processing.

High-resolution mass mass spectrometry is an ideal technique for identifying and determining the elemental and isotopic contents of a sample with high levels of precision. The technique generally cannot determine the difference between geometric isomers of organic compounds with the same exact masses.