Buy Chemicals Online By Searching For Their CAS Registry Number

Buy Chemicals Online By Searching For Their CAS Registry Number

If you are using a laptop or desktop computer, you can use the search box in the top right corner of the website to search for chemicals by their name, chemical formula or CAS Registry Number (CASRN, CAS Number, CAS #). 

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Common CAS Numbers

Chemical Formulas

A chemical formula is a way of presenting information about the chemical proportions of atoms that constitute a particular chemical compound or molecule, using chemical element symbols, numbers, and sometimes also other symbols, such as parentheses, dashes, brackets, commas and plus (+) and minus (−) signs. For example, the chemical formula for Nitric Acid is HNO3. A CAS Registry Number, also referred to as CASRN or CAS Number, is a unique numerical identifier assigned by the Chemical Abstracts Service (CAS) to every chemical substance described in the open scientific literature (currently including all substances described from 1957 through the present, plus some substances from the early or mid 1900s), including organic and inorganic compounds, minerals, isotopes, alloys and nonstructurable materials (UVCBs, substances of unknown or variable composition, complex reaction products, or biological origin).

The registry maintained by CAS is an authoritative collection of disclosed chemical substance information. It currently identifies more than 144 million unique organic and inorganic substances and 67 million protein and DNA sequences, plus additional information about each substance. It is updated with around 15,000 additional new substances daily.

Where Can I Find A CAS Number?

The CAS Registry Number is the universally recognized unique identifier of chemical substances and is often found on packaging and on articles of commerce. To find a CAS Number, click here.

Common Chemistry™ from Chemical Abstracts Service (CAS), a web resource that contains CAS Registry Numbers for approximately 7,900 chemicals of widespread general public interest. Common Chemistry is helpful to non-chemists who know either a name or CAS Registry Number® of a common chemical and want to pair both pieces of information. The CAS Registry Number is the universally recognized unique identifier of chemical substances and is often found on packaging and on articles of commerce. While not a comprehensive CAS Registry Number lookup service, Common Chemistry does provide a way to quickly and easily find names or CAS Registry Numbers for chemicals of general interest.  CAS has collaborated with Wikipedia in developing this resource and encourages you to use the Wikipedia link (when available) or other sources of general information on chemistry, to learn more about these chemicals.

Do Mixtures Have A CAS Number?

Although a single CAS RN (Registry Number) is not normally assigned to an intentional mixture, CAS RNs are provided for the individual components of the mixture. CAS will assign a single CAS RN to a substance regardless of varying physical forms, except for naturally occurring minerals. For example, water, ice, and water vapor are all represented by CAS RN 7732-18-5. CAS will register specific alloys, ions, isotopes, and elementary particles.

CAS REGISTRY | The Gold Standard For Chemical Substance Information

CAS REGISTRY 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 the following:

  • 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.