The library search algorithm implemented in the jHRMS toolbox is ULSA (Section S1.4). This algorithm provides extensive reporting on the match quality (Section S1.4). In total, there are 7 parameters that are used to provide a final score, for which the weights of each quality reporting parameter can be set. The algorithm can be used with either the provided database, containing MassBank EU, 38 MassBank of North America, 39 and GNPS, or a local database in a specified format. Finally, the implemented suspect screening algorithm (S1.5) allows for screening of MS/MS spectra. Initially it screens for the precursor ion and records all instances the precursor ion were found, including which fragments from the reference spectrum were matched and a matching score. Additionally, a suspect list with MS2 information can be easily constructed with InChIKeys or SMILES from the internal database.