The Glyco MS Calculator is a tool to aid in the analysis of glycoforms, e.g. glycans and glycopeptides. The user inputs the number of residues in the glycan and the program calculates for the masses and elemental composition of the glycan. It also calculates for the derivatized masses, e.g. permethylated or 2-AB labeled, of the glycan. Then, it generates the monoisotopic masses of molecular ion adducts often observed in ESI mass spectra.