How to Read a Certificate of Analysis (COA)

A Certificate of Analysis is the single most useful document a research compound supplier can give you — if you know what to look for. Here's a section-by-section breakdown.

1. Compound Identity

The COA should clearly state the compound tested and confirm its identity matches the product label. Look for the testing method used to confirm identity (commonly HPLC — high-performance liquid chromatography — for small-molecule compounds).

2. Batch or Lot Number

Every legitimate COA is tied to a specific production batch, not a generic template reused across every sale. This number should match what's printed on your product packaging, allowing you to trace your specific unit back to its exact test results.

3. Purity Percentage

This is the headline number most buyers look for first — but it's worth checking that it's reported alongside a testing method, not just stated as a bare percentage with no methodology behind it.

4. Testing Laboratory

A COA should name the laboratory that performed the testing. Independent, third-party labs (not owned or operated by the manufacturer) provide a meaningful check the manufacturer's own internal specs can't.

5. Date of Testing

Testing dates help confirm the COA corresponds to a recent, relevant production run rather than an outdated or unrelated reference sample.

Red Flags to Watch For

  • A COA with no batch/lot number
  • No named testing laboratory, or a lab that appears to be affiliated with the seller
  • The same COA reused across completely different product listings
  • No testing method disclosed alongside the purity number

Why We Publish Ours

We provide our most recent independent lab report directly on our site so customers can verify our documentation before purchasing, not just after.

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