Cytosolic calcium signals play important roles in processes such as cell growth and motility, synaptic communication and formation of neural circuitry. These signals have complex time courses and their quantitative analysis is not easily accomplished; in particular it may be difficult to evidence subtle differences in their temporal patterns. In this paper, we use wavelet analysis to extract information on the structure of [Formula: see text] oscillations. To this aim we have derived a set of indices by which different [Formula: see text] oscillatory patterns and their change in time can be extracted and quantitatively evaluated. This approach has been validated with examples of experimental recordings showing changes in oscillatory behavior in cells stimulated with a calcium-releasing agonist.