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Testing & Purity

How to Read a Certificate of Analysis (COA) — Step by Step

Certificates of Analysis (COAs) can look intimidating. This step-by-step guide breaks down every section, so researchers know exactly what to look for and what red flags to avoid.

May 20, 2026 | 5 min read
What Is a COA?

A Certificate of Analysis (COA) is a document issued by a testing laboratory that reports the results of analytical testing performed on a specific batch of a compound. A legitimate COA should be batch-specific (not a generic template), issued by an independent third-party laboratory, and include the lab’s name, accreditation number, analyst signature, and test date.

A COA is only as trustworthy as the lab that issued it. Always check that the issuing laboratory is accredited (ISO/IEC 17025 or equivalent) and that the document includes the lab’s contact information so you can verify authenticity if needed.