SpectrumLook can be used to inspect the fragmentation (MS/MS) spectra in an LC-MS/MS analysis. It reads Finnigan .Raw files, .mzXml files, or .mzData files, plus a "Synopsis File" listing peptides identified by a MS/MS interpretation tool like SEQUEST or X!Tandem. The software allows users to visually browse the MS/MS spectra that led to the peptide identifications, including viewing annotations for the identified b and y ions, plus neutral loss ions where appropriate.

This software will compute the theoretical ion m/z values based on a peptide sequence, then compare the theoretical m/z values to observed m/z values, labelling peaks that match within a tolerance (defaults are +/-0.5 for neutral loss and +/-0.7 for m/z values).

The license of this software is Freeware, you can free download and free use this calculator software.