How to read a batch Certificate of Analysis
A COA describes analytical results for an identified sample or batch. Read the document itself and connect it to the lot on the product.
LifeSpanSupply · Updated 7 November 2026
1. Match the report to the product
Check compound name, lot or batch number, sample identifier and report date. A report for a different lot is not documentation for the container in front of you. On a product page, use the batch-documentation section or contact support with the product name and lot number.
2. Read methods, limits and actual results
A useful certificate identifies which tests were performed, the methods, specifications or limits, and the reported results. A numerical purity result, an identity result and a measured content result answer different questions. Do not treat a general quality badge as a substitute for the report.
3. Separate purity, identity and amount
Chromatographic purity describes the reported chromatographic analysis. Identity testing asks what compound was detected. Content or assay addresses quantity under its stated method. A headline purity percentage does not answer every one of these questions. Read the units and method next to each result.
4. Check what was not tested
Do not infer sterility, endotoxin levels, stability or suitability for an intended use from an HPLC percentage. Look for the relevant test and result. Where a report does not contain a result, ask for the applicable documentation rather than assuming a pass.
Keep the link to your batch
Save the original report with the lot information for your records. If identifiers, dates or results are unclear, ask the supplier or issuing laboratory for clarification. Testing information supports traceability; it does not turn a research product into an approved medicine.