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NIST Standard Reference Database 1A v17


NIST/EPA/NIH Mass Spectral Library with Search Program
Data Version: NIST v17
Software Version: 2.3

This database is the product of an ongoing comprehensive evaluation and expansion of the world's most widely used mass spectral reference library.

(NIST SRD 1A is available ONLY from distributors)

Contents of the NIST 17 Mass Spectral and Retention Index Libraries
Library Description Library File Name Library Contents
NIST/EPA/NIH Mass Spectral Library (EI)
Main EI MS Library mainlib Spectra for 267,376 chemical compounds
Replicate EI MS Library replib 39,246 replicate spectra
Tandem (MS/MS)Library

Tandem (MS/MS) Library - small molecules

nist_msms 574,826 spectra of 118,082 precursor ions from 13,808 chemical compounds
Tandem (MS/MS) Library - biologically-active peptides  nist_msms2 90,244 spectra of 6,803 precursor ions from 1,904 peptides
GC Method / Retention Index Library
Retention Index Library


404,045 RI values for 99,400 compounds; 72,361 compounds in the Main Library have retention index data.


  • Tandem (MS/MS) Library and GC Method / Retention Index Library may be obtained as separate products.

Evaluation and Quality Control

  • Each spectrum critically examined by experienced mass spectrometrists.
  • Each chemical structure examined for correctness and consistency, using both human and computer methods.
  • Spectra of all stereoisomers intercompared.
  • Chemical names examined by experts and IUPAC names provided.
  • Thousands of spectra replaced with higher quality measurements.
  • Verified CAS registry numbers.

For more information, please visit

The scientific contact for the database is:

Stephen E. Stein
Mass Spectrometry Data Center
National Institute of Standards and Technology
Gaithersburg, MD 20899-8362
(301) 975-2505

Keywords: analysis; chemical analysis; chemical databases; chemical structure; chemistry; mass spectra; mass spectrometry.


Standard Reference Data, NIST:
100 Bureau Drive, Stop 6410
Gaithersburg, MD 20899-6410
Tel: 844-374-0183 (Toll Free)

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Created June 19, 2014, Updated April 3, 2020