1. Who tested it, and which report this is
The header names the laboratory and gives a report, certificate or accession number. That number is how you look the report up on the lab’s own site (see how to verify a report). No lab name or no number means you can’t check it.
2. What was tested
The sample section should name the product, the labeled amount per vial and the lot number. The lot number ties the report to one production batch, and it should match the label on the vial you receive. A report without a lot number describes a sample, not your vial.
3. Identity: is it what the label says?
Identity is usually confirmed by mass spectrometry (MS), often coupled with liquid chromatography (LC-MS). The report compares the molecular mass the lab observed with the expected mass of the labeled compound. A match confirms the molecule. Purity alone does not: a sample can be very pure and still be the wrong compound.
4. Purity: how clean is it?
Purity is usually measured by high-performance liquid chromatography (HPLC), often with UV detection (HPLC-UV). The result is the share of the measured signal that belongs to the main compound, for example 99.27%. Look for the method written next to the number and, ideally, the chromatogram. A bare percentage with no method gives you nothing to judge.
5. Content: how much is in the vial?
Some reports also state the measured amount against the labeled amount (for example mg found per vial). Not every report includes it, so check which tests were actually run.
6. Endotoxin
An endotoxin result shows whether the sample passed a bacterial endotoxin test, commonly the USP <85> method. Reports may give a value in endotoxin units (EU) or a pass against a limit. See endotoxin testing, explained.
7. Dates and sign-off
A report should show when the sample was received and tested, and who released it. The test date should make sense for the lot being sold.
What a COA can’t tell you
- Whether your vial came from the tested lot, unless the lot numbers match.
- Anything about lots that weren’t tested.
- How the product was stored or shipped after testing.
- Anything about use in people or animals. Analytical reports describe a sample, nothing else.
A real example
Arctic’s October 2026 reports from Freedom Diagnostics show all of the above on one page: LC-MS identity, HPLC-UV purity, an endotoxin pass on USP <85> (2 replicates), the lot number and a lookup code. Open the BPC-157 10MG lot BP-2501A report and compare it line by line with this guide.
Check ours yourself. Every current report is public, with the lot number and a link to the lab’s own verification page.
Questions
What does HPLC purity mean on a peptide COA?
HPLC purity is the share of the measured chromatography signal that belongs to the main compound, for example 99.3%. It says how clean the sample is, not whether the molecule is the right one. Look for the method next to the number.
What does mass spectrometry show on a COA?
Mass spectrometry (MS or LC-MS) compares the molecular mass observed in the sample with the expected mass of the labeled compound. A match confirms identity, which purity alone cannot do.
Why does the lot number matter?
The lot number ties the report to one production batch. If it doesn't match the label on your vial, the report doesn't describe what you received.
Is a COA without a lab name valid?
You can't check it. A useful report names the laboratory and gives a report or accession number you can look up on the lab's own website.
Does every COA include endotoxin testing?
No. Endotoxin is a separate test. Check the report's list of tests; Arctic's Freedom Diagnostics reports from October 2026 include an endotoxin result.