Abstract: The present invention relates to a new method for classification of spectral data comprising: a. analyzing at least two samples belonging to at least one cluster through recording of a spectrum; b. for each spectrum determining the peaks and the spectral value at which they occur; c. calculating the probability (p) of occurrence for each peak for every cluster and from this the odds ratio p/(1?p) for each peak; d. preparing a spectrum from a sample to be classified with the same technique as in step a); e. determine the peaks in the spectrum obtained in step d); f. calculate the likelihood of identity for each cluster by multiplying per cluster the odds ratio in said cluster for each peak found in the spectrum of step d); and g. assign the sample tested in step d) to the cluster that provides the largest number as a result of step f). The invention also comprises a system for performing such a method and the use of such a system for classification of spectral data.