How to Read a Hemp Certificate of Analysis
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A certificate of analysis, usually called a COA, records laboratory findings for an identified sample. Reading one carefully means checking more than the largest percentage or a green “Pass” label.
Start with the sample details
Find the laboratory name, report number, sample identification, product description, batch or lot number, and testing dates. Compare those details with the information accompanying the material. A report for a similarly named product is not automatically a report for the same batch.
Check the document's page count, too. A summary page may not include the individual results, methods, or explanations needed to interpret it.
Read the full cannabinoid table
Look at each reported compound rather than relying on a single “total” figure. Delta-9 THC, THCA, CBD, and other cannabinoids can appear on separate rows. A total may be calculated from selected compounds rather than every substance listed.
Read the equation or footnote defining that total. USDA's hemp-production testing guidance, for example, accounts for the potential conversion of THCA into delta-9 THC. That production-testing framework should not be confused with a complete assessment of a finished product.
Check the units and reporting basis
Percent, milligrams per gram, and milligrams per package describe different quantities. For a mass-based concentration, 1% equals 10 milligrams per gram. A package total also depends on the amount of material in the package.
Look for whether results are reported on a dry-weight or as-received basis. Comparisons are more meaningful when the units and reporting basis match.
Review what was actually tested
A cannabinoid panel does not establish pesticide, heavy-metal, or microbial results. Look for the individual panels and any “not tested” entries. If the headline, individual rows, or units appear inconsistent, ask the issuing laboratory for clarification before drawing conclusions.
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