The NIST / EPA / NIH EI Mass Spectral Library 2026, developed by the National Institute of Standards and Technology (NIST), is one of the world's most trusted mass spectral libraries for GC-MS compound identification. Built on more than four decades of development, the 2026 release contains over 431,000 critically evaluated EI spectra representing more than 376,000 unique compounds, supporting reliable identification across environmental, forensic, pharmaceutical, food, and industrial applications.
The library includes the Electron Ionization (EI) Mass Spectral Library, GC Retention Index (RI) Library, and the NIST 2026 software suite featuring MS Search, AMDIS, and MS Interpreter. New in this release is integrated GC-MS chromatogram analysis, streamlining data processing and library searching within a single workflow.
The updated GC Retention Index Library now contains more than 527,900 RI values, while the EI library has been expanded with over 35,000 new compounds, focusing on biologically, environmentally, and industrially relevant analytes.
Available from Wiley in native formats for most major GC-MS instrument vendors, NIST 2026 is compatible with current and legacy mass spectrometry data systems and can also be supplied in bundles with KnowItAll software.
