Mass Spectral Library, The Databases

Spectra in the NIST Mass Spectral Library may have information including formula, mass (nominal, exact, or both) names and synonyms, structures, and more

There is a reason that we call the NIST Mass Spectral Library the most trusted database in mass spectrometry.


The peer reviewed libraries contain spectra, structures and extensive reference data from a number of sources including contributors, compounds measured at NIST, and spectra extracted from the literature.

The NIST/EPA/NIH Mass Spectral Library

This release contains 306,622 electron ionization (EI) spectra (mainlib and replib) of 267,376 different chemical compounds – an increase of over 30,000 spectra and nearly 25,000 compounds from NIST 14. For this release, special effort has been made to add spectra for human and plant metabolites as well as for illicit ‘designer drugs’, leading to the addition of 1000s of spectra. The evaluation of this library has employed newly-developed search methods, some of which are implemented in the accompanying software and described above.

The NIST Tandem Mass Spectral Library

This portion of the NIST 2017 has had the most enhancements.

Small molecules (nist_msms): Includes 574,826 spectra of 118,082 precursor ions for 13,808 different compounds – a 2/3 increase in numbers of compounds over NIST 14! Spectra of all identifiable precursor ions are included, including fragments, adducts, and isotopic chlorine and bromine peaks. We continue to include spectra for both positive and negative charge states, with fragmentation in both ion trap (at multiple msn levels) and in beam-type collision cells (over a range of energies).

Biologically relevant peptides (nist_msms2): Includes 77,649 spectra of 1,435 biologically relevant peptides. Also included are 12,595 spectra of 469 dipeptides also in nist_msms.

The Gas Chromatography Retention Index and Methods Library

This contains 404,045 retention indices for 99,400 compounds, including 72,361 of which are in the EI library. This is an increase of 16,582 RI values.

Click here to order the Full Version NIST/EPA/NIH (NIST 17) Mass Spectrometry Database…

Click here to order the Upgrade Version NIST/EPA/NIH (NIST 17) Mass Spectrometry Database*…

*NIST 2017 upgrades are complete databases, and are available to anyone who has prior ownership of NBS 98, NIST 02, NIST 05, NIST 08 NIST 11, or NIST 14.

Before we deliver your software, via FTP, DVD OR USB, we will ask for a screen capture to verify ownership. An easy way is to open MS Search, Click Help, go to About NIST, and do CTL Print screen. An example may be found at

Mass Spectral Interpretation Courses Available

Get the Most Out of Your NIST Mass Spectral Library

Have you wondered whether you are getting the best results from your NIST searches? Are there other ways to confirm the identity of your unknown compound? Wouldn’t it be nice to be able to read a spectrum? What is this hybrid search, anyway?

The answers to these questions and more are available through Available either in a classroom setting, or Live-on-the-web, or self-paced, there is a format that will fit your location, schedule, and learning goals.

The Mass Spectral Interpretation Course is conducted by O. David Sparkman who is currently an Adjunct Professor of Chemistry at the University of the Pacific in Stockton, California; Contractor to the National Institute of Standards and Technology Mass Spectrometry Data Center; President of; and a former American Chemical Society Instructor (1978–2006) and American Society for Mass Spectrometry Member-at-large for Education (2004–2006).

To learn more, visit the Mass-Spec-Training web site by clicking here: