COA Basics
What a COA Is
A Certificate of Analysis is a batch-specific document that summarizes testing information for a material. It may include identity, purity, method, batch number, date, and lab information.
Resources / COA Education
COA Education
Learn the basics of batch documentation, purity reports, identity testing, and common COA warning signs.
This page is for general laboratory education only. A COA does not prove a material is safe, legal, approved, sterile, or appropriate for human use.
The Basics
Reading a COA
A COA should be batch-specific, readable, and tied to actual analytical testing.
COA Basics
Batch Numbers
A batch number connects a product or material to a specific production or testing record. The batch number on a vial, label, or package should match the batch number on the COA.
COA Basics
Purity Results
Purity is usually shown as a percentage from analytical testing. Higher purity does not automatically mean a material is appropriate for human use or any medical purpose.
COA Basics
Testing Methods
Common terms include HPLC, LC-MS, Mass Spec, and chromatogram. These methods help support identity and purity claims when performed by a qualified lab.
Warning Signs
COA Red Flags
These issues do not automatically prove something is wrong, but they are reasons to slow down and verify.
Common red flags
- No batch number listed.
- Batch number does not match the label or package.
- No testing date or outdated testing date.
- No lab name, lab contact, or testing method listed.
- Only a marketing claim is shown instead of actual test data.
- The COA image looks edited, cropped, blurry, or incomplete.
- The seller refuses to provide batch-specific documentation.
- Purity or identity claims are made without supporting details.
Important limitation.A COA is only one piece of documentation. It should not be treated as medical approval, FDA approval, legal clearance, sterility confirmation, or proof that a material is appropriate for human use.
Quick Glossary
Common Testing Terms
Basic terms users may see when reviewing batch documentation.
HPLC
High-performance liquid chromatography. Often used to separate and measure components in a sample.
LC-MS
Liquid chromatography–mass spectrometry. Often used to support identity and composition testing.
Mass Spec
Mass spectrometry. A method that can help identify molecular weight and support identity claims.
Chromatogram
A graph produced by chromatography testing. Peaks can represent detected components in a sample.
Identity
Testing intended to support that the material is what it is claimed to be.
Purity
A measurement of how much of the detected sample appears to be the target material under the testing method used.
Educational only.This glossary is simplified for public learning. Users should verify technical interpretation with qualified laboratory, regulatory, or healthcare professionals when accuracy matters.