CAS REGISTRY - The gold standard for chemical substance information

CAS REGISTRYSM contains more than 157 million unique organic and inorganic chemical substances, such as alloys, coordination compounds, minerals, mixtures, polymers and salts, and more than 68 million sequences - more than any other database of its kind.

When you need to positively identify a chemical substance, you can rely on the authoritative source for chemical names and structures of CAS REGISTRY. You can also identify your substance of interest by its CAS Registry Number®, which is universally used to provide a unique, unmistakable identifier for chemical substances. If your organization uses CAS Registry Numbers to help others locate accurate chemical information, please refer to the CAS RN Verified Partner Program information to ensure appropriate licensing and use.

You can also use CAS REGISTRY to locate

  • literature references to the substance
  • experimental and predicted property data (boiling and melting points, etc.)
  • CA Index Names and synonyms
  • commercial availability
  • preparative methods
  • spectra
  • regulatory information from international sources

You can obtain the information you need for millions of substances from the most current and reliable collection of chemical substance information in the world, CAS REGISTRY.


Substances reported in the literature back to the early 1800s.

Updated daily.

Substance information enriched with experimental and predicted property data, including  ~8 billion property values, data tags and spectra.

The CAS REGISTRY database contains records for specific substances identified by the Chemical Abstracts Service (CAS) REGISTRY system.

All substance records contain a unique CAS Registry Number. Records may also have CA index names, synonyms, structure diagrams, stereochemistry, molecular formulas, ring data, alloy composition tables, protein and nucleic acid sequences, classes for polymers, and the number of references in the CA/CAplus databases. All of this information is displayable and searchable on STN, but some of it is only displayable in SciFinder.

In addition to substance information, REGISTRY records contain super roles and document type information from CAplus, experimental and predicted (calculated) property data, and tags pointing to references containing experimental property data. 

Sample record from SciFindern

Lisinopril structure from SciFinder-n


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