How to Read a Certificate of Analysis
A Certificate of Analysis needs to identify the material and show the results relevant to it. Read the product and lot connection before interpreting any percentage. This guide explains the fields; it is not a certificate for a Knockout Labs product or lot.
Identify the document and the material
Record the report reference, issuer, issue date and version as shown. Check the product name and the attributes needed to distinguish its form or variant. Compare the lot on the report with the lot on the container and order records.
A laboratory sample number may differ from the supplier’s lot number. That is not automatically an error, but the relationship needs documentation. Matching a certificate to a batch explains how to examine the connection without guessing.
Read each result across the row
| Field | Question to answer |
|---|---|
| Test | What attribute was examined? |
| Procedure or method | How was that attribute measured or assessed? |
| Result | What was actually reported, with its units or basis? |
| Acceptance criterion | What requirement was used for comparison? |
| Comment or qualification | Does a limitation change the interpretation? |
ICH Q7 identifies batch details, tests, acceptance limits and results as relevant certificate information within pharmaceutical API guidance. That provides a useful reading framework without establishing a research supplier’s GMP status. [1]
Keep identity, purity and quantity distinct
A purity percentage is not an identity result. An HPLC area percentage is not automatically the target compound’s fraction of the container’s total mass. A nominal fill on a label is not a quantitative assay. Read the identity, purity and assay guide before treating these fields as interchangeable.
The method also matters. A result described only as “passes” may answer less than a numerical result with a stated criterion. Ask what the reported conclusion covers rather than supplying the missing detail yourself. Analytical testing methods explains the main distinctions.
A fictional mismatch to practise on
Suppose DEMO-REPORT-7 names DEMO-LOT-A while your invented container ledger says DEMO-LOT-B. Record the mismatch exactly. Do not use the report’s favourable purity result to close it. Ask for the matching report or the documented relationship between the identifiers.
If a corrected version arrives, preserve the earlier record and note which version supersedes it. This example is an original teaching illustration; its identifiers and situation are invented and do not describe an actual lot.
Decide what remains unanswered
List unresolved fields separately: lot connection, method basis, identity evidence, quantity basis or the applicable decision. Request the specific record through batch documentation. A report may be useful for one question and silent on another.
Use the quality hub for the next explanation. No certificate should be treated as evidence of suitability for human or veterinary administration.
Use the generic and reused certificate checklist when a report's scope, identifiers or presentation need further explanation.
Supporting checks
| Resource | Why open it |
|---|---|
| Manufacturer Certificates and Independent Laboratory Reports | Distinguish who issued a certificate and what independence means. |
| Why a Purity Percentage Does Not Prove Identity | Understand why a purity percentage cannot establish identity. |
| Our Purity Claim and How It Is Substantiated | Examine the basis and limits of the 99%+ purity claim. |
Sources and scope
- Q7 Good Manufacturing Practice Guidance for Active Pharmaceutical IngredientsBatch identification, performed tests, acceptance criteria and numerical results in certificates. Access: Opened official PDF; relevant passages read Limits: Pharmaceutical API guidance; no actual supplier numbering, record completeness or GMP compliance inferred.