This function determines which compounds are most closely matched to either: 1) a given EI-MS spectrum; or 2) a given Kovats RI or 3) a given Kovats RI and EI-MS spectrum. Users must select a database (5 options are provided) to search the given input data. The EI-MS spectrum must be entered as a list typed into the data submission box with the m/z value in the first column and the normalized intensity (1-1000) in the second column. Top candidates are ranked according to how closely they match and returned in a list.