Advances in spectral libraries for LC-MS/MS based untargeted metabolomics. (a) The GNPS community spectral libraries (non-commercial only) have grown from 23,790 MS/MS spectra in 2014 to 586,647 MS/MS spectra in 2022 (September 2022). Concurrently, the number of library spectra that matched to public data has grown from 4,727 MS/MS spectra in 2014 to 127,405 MS/MS spectra in 2022 (22% of the publicly available library spectra have matches to experimental MS/MS spectra in public data). (b) Fueled by growing spectral libraries, the MS/MS spectrum annotation rate for the GNPS continuous identification mode as part of living data (M. Wang et al., 2016), which periodically reanalyses all public datasets on GNPS/MassIVE with the latest spectral libraries, has increased from 2% of MS/MS spectra on average in 2014 to 13% in 2022.