CAS REGISTRY®, the CAS substance collection, is the premier source relied upon by scientists and regulators worldwide for accurate information on chemical substances.

CAS Registry Numbers (CAS RN) are simple and regular, convenient for database searches. They offer a reliable, common and international link to every specific substance across the various …

“CAS registry” is a registered trademark of the American Chemical society.

Dec 1, 2025 · Chemical Abstracts Service (CAS) has a registry system for all completely identified chemical compounds or substances. There are over 144 million chemical substances & sequences …

Dec 16, 2025 · 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.

Dec 26, 2025 · CAS registry numbers are used for searching chemical databases. The size of the registry is immense, with over 32 million substances and 59 million sequences. It identifies every …

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