A method for identifying a species of an unidentified polymeric chemical compound comprising repeating structural units and one or more end units, the method comprising: accessing mass spectrometry data that relates to a sample comprising the unidentified polymeric chemical compound; identifying, from the mass spectrometry data, an estimated mass of the unidentified polymeric chemical compound; determining an estimated mass of the portion of the unidentified polymeric chemical compound made up of the repeating structural units; and identifying, by a processor of a computing device, one or more candidate chemical formulas for the unidentified polymeric chemical compound based on: (i) the mass spectrometry data for the unidentified polymeric chemical compound, (ii) the estimated mass of the unidentified polymeric chemical compound; and (iii) the estimated mass of the portion of the unidentified polymeric chemical compound made up of the repeating structural units, wherein identifying the one or more candidate chemical formulas for the unidentified polymeric chemical compound comprises iteratively adding combinations of possible elements to identify a plurality of candidate element combinations for the one or more end units, wherein a calculated mass of each candidate element combination of the plurality of candidate element combinations, when summed with the estimated mass of the portion of the unidentified polymeric chemical compound made up of the repeating units, is within a threshold mass of the estimated mass of the unidentified polymeric chemical compound, wherein each repeating structural unit has the same chemical formula, and the one or more end units has a chemical formula different than the chemical formula of the repeating structural units. accessing mass spectrometry data that relates to a sample comprising the unidentified polymeric chemical compound; identifying, from the mass spectrometry data, an estimated mass of the unidentified polymeric chemical compound; determining an estimated mass of the portion of the unidentified polymeric chemical compound made up of the repeating structural units; and identifying, by a processor of a computing device, one or more candidate chemical formulas for the unidentified polymeric chemical compound based on: (i) the mass spectrometry data for the unidentified polymeric chemical compound, (ii) the estimated mass of the unidentified polymeric chemical compound; and (iii) the estimated mass of the portion of the unidentified polymeric chemical compound made up of the repeating structural units, wherein identifying the one or more candidate chemical formulas for the unidentified polymeric chemical compound comprises iteratively adding combinations of possible elements to identify a plurality of candidate element combinations for the one or more end units, wherein a calculated mass of each candidate element combination of the plurality of candidate element combinations, when summed with the estimated mass of the portion of the unidentified polymeric chemical compound made up of the repeating units, is within a threshold mass of the estimated mass of the unidentified polymeric chemical compound, wherein each repeating structural unit has the same chemical formula, and the one or more end units has a chemical formula different than the chemical formula of the repeating structural units. (i) the mass spectrometry data for the unidentified polymeric chemical compound, (ii) the estimated mass of the unidentified polymeric chemical compound; and (iii) the estimated mass of the portion of the unidentified polymeric chemical compound made up of the repeating structural units, wherein identifying the one or more candidate chemical formulas for the unidentified polymeric chemical compound comprises iteratively adding combinations of possible elements to identify a plurality of candidate element combinations for the one or more end units, wherein a calculated mass of each candidate element combination of the plurality of candidate element combinations, when summed with the estimated mass of the portion of the unidentified polymeric chemical compound made up of the repeating units, is within a threshold mass of the estimated mass of the unidentified polymeric chemical compound, wherein each repeating structural unit has the same chemical formula, and the one or more end units has a chemical formula different than the chemical formula of the repeating structural units. wherein identifying the one or more candidate chemical formulas for the unidentified polymeric chemical compound comprises iteratively adding combinations of possible elements to identify a plurality of candidate element combinations for the one or more end units, wherein a calculated mass of each candidate element combination of the plurality of candidate element combinations, when summed with the estimated mass of the portion of the unidentified polymeric chemical compound made up of the repeating units, is within a threshold mass of the estimated mass of the unidentified polymeric chemical compound, wherein each repeating structural unit has the same chemical formula, and the one or more end units has a chemical formula different than the chemical formula of the repeating structural units.