A COA, or certificate of analysis, is a lab test report. Before reading the results, check whether the report is genuine and whether it covers the sample and batch being claimed.
1. Get the complete report
Ask for the lab name, report number, date, sample name, lot or batch code, and any verification key. A cropped screenshot of “99%” is not enough. A report image can be copied or edited; appearance alone cannot establish authenticity.
2. Find the lab independently
Use the laboratory’s own official website, rather than relying only on the seller’s image or a QR code. Check the web address carefully. If the report is from Janoshik, its official verification page asks for the task number and unique key.
If the lab has no public checker, use contact details from its official website to ask whether it issued the report. Avoid sending private information to an unverified contact.
3. Compare the original, seller, and vial
Check the full compound name, batch code, date, results, and client or sample-submitter details when shown. A client name may be a manufacturer or intermediary rather than the storefront. Ask the seller to explain that connection; a different name alone does not prove fraud.
If the online original differs from the screenshot, or the key does not open the claimed report, pause and ask the lab for clarification. A valid report for someone else’s material does not establish the identity of your vial.
4. Read what was actually tested
- Identity: Is the tested substance the named compound?
- Purity: How much of the measured test signal came from the main substance?
- Content: How many mg were measured?
- Sterility: Was a separate test done for living germs?
- Endotoxins: Was a separate test done for certain bacterial toxins?
These answer different questions. 99% purity does not mean a 10 mg vial contains 9.9 mg. A purity graph does not prove sterility or the absence of endotoxins. Our dictionary explains the test names.
5. Understand the remaining gap
A genuine report describes the sample the lab received. Check how that sample connects to the batch and seller. It cannot guarantee every vial, shipping conditions, a health benefit, or a safe dose for a person.
Practice with a sample report
This example is invented for learning. It is not a real COA or a recommendation to buy or use a product.
- Vial and seller listing: “Compound A,” labeled 10 mg, lot A-104.
- Lab’s original report: report R-248, sample “Compound A,” lot A-104, with a testing date. The lab confirms that it issued R-248.
- Reported tests: HPLC main-peak area 99%; mass-spectrometry result consistent with the expected mass.
- Not reported: a quantitative peptide-content result in mg, sterility, and endotoxins.
What can you conclude?
The matching name, lot, and report number connect the paperwork to a submitted sample, assuming the seller can explain how that sample connects to its inventory. The HPLC result describes a proportion of the measured chromatogram signal under the lab’s method. The mass-spectrometry result adds evidence about identity. These are different tests.
What can’t you conclude?
The report does not establish that the vial contains 9.9 mg or even verify its labeled 10 mg, because no quantitative mg result was reported. It does not establish sterility or endotoxin status, because those tests were not reported. It does not prove that every vial from the lot is identical to the sample or suitable for a person. If the report cannot be opened or confirmed through the real lab, even the apparent match needs further checking.
What if one field is missing?
Write down the missing field and ask a specific question. “Can the lab confirm report R-248?” is different from “Can the seller connect lot A-104 to the sample in R-248?” If the seller cannot answer, do not fill the gap with assumptions. Use the five-check COA checklist to repeat the same process with a real document.
Why the test names are separate
Analytical guidance distinguishes identity, assay or amount, purity, and impurity measurements. A method must fit the question it is used to answer. That is why one attractive percentage cannot stand in for a complete report. The ICH analytical-procedure guideline makes these distinctions for regulated drug testing; its scope does not turn a research vial into an approved medicine. NIST explains liquid chromatography, and its mass-spectrometry resource explains the separate mass measurement.
A fuller report example
JD BioWorks’ field-by-field COA article explains the report fields. Its HPLC graph article covers the graph. Follow the underlying lab records; a supplier’s explanation does not replace verification.
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