MACE is an open-access add-on data repository of EI-MS spectra available at https://doi.org/10.24355/dbbs.084-202402071310-0. The latest release is mace_r5.1 http://www.oc.tu-bs.de/schulz/html/MACE_en.html. We currently prepare release 6 of the GC/MS database MACE with about 300 spectra. If you want to include some additions, please contact: mace@tu-braunschweig.de