A method for extracting mass information from low resolution mass-to-charge ratio spectra of multiply charged species to identify a mass of a polyatomic parent molecule within the multiply charged species, the method comprising the steps of: receiving from a mass spectrometer a data set indicative of a population of multiply charged ions, the number of charges on each ion defining the charge state of that ion, wherein a sub-population of ions within said population of ions comprises ions of said population of ions having a same charge state; using the data set indicative of a population of multiply charged ions to produce an input mass-to-charge ratio spectrum, the sub-populations of each charge state being represented by intensities in the mass-to-charge ratio spectrum; processing the input mass-to-charge ratio spectrum to provide a signal enhanced mass-to-charge ratio spectrum, the signal enhanced mass-to-charge ratio spectrum being generated from a logarithm of the quotient of said mass-to-charge ratio spectrum and a smoothed representation of said mass-to-charge ratio spectrum; identifying a range of defined charged mass values of a defined charged mass spectrum within which to search for a mass of the polyatomic parent molecule; generating for each mass within said range of defined charged mass values a summation equal to the addition of values in the signal enhanced mass-to-charge ratio spectrum that correspond to said mass at sequential charge states up to a maximum charge state using the function: F M = ∑ n = 1 n = n max X M − zm a n + m a where M is any defined mass within said range of defined charged mass values; m a is the mass of the charge carrying adduct; z is the order of the defined charged mass spectrum and X is a distribution function of the signal enhanced mass-to-charge ratio spectrum; and using said summation values to determine the mass of a polyatomic parent molecule. receiving from a mass spectrometer a data set indicative of a population of multiply charged ions, the number of charges on each ion defining the charge state of that ion, wherein a sub-population of ions within said population of ions comprises ions of said population of ions having a same charge state; using the data set indicative of a population of multiply charged ions to produce an input mass-to-charge ratio spectrum, the sub-populations of each charge state being represented by intensities in the mass-to-charge ratio spectrum; processing the input mass-to-charge ratio spectrum to provide a signal enhanced mass-to-charge ratio spectrum, the signal enhanced mass-to-charge ratio spectrum being generated from a logarithm of the quotient of said mass-to-charge ratio spectrum and a smoothed representation of said mass-to-charge ratio spectrum; identifying a range of defined charged mass values of a defined charged mass spectrum within which to search for a mass of the polyatomic parent molecule; generating for each mass within said range of defined charged mass values a summation equal to the addition of values in the signal enhanced mass-to-charge ratio spectrum that correspond to said mass at sequential charge states up to a maximum charge state using the function: F M = ∑ n = 1 n = n max X M − zm a n + m a where M is any defined mass within said range of defined charged mass values; m a is the mass of the charge carrying adduct; z is the order of the defined charged mass spectrum and X is a distribution function of the signal enhanced mass-to-charge ratio spectrum; and using said summation values to determine the mass of a polyatomic parent molecule.