COA Checker: Work Out What a Certificate Actually Says

A certificate of analysis is only useful if you can do three things with it: work out how much peptide is actually in the vial, tie the report to the lot you are holding, and compare one vendor’s figures with another’s on the same basis. The calculators below do that arithmetic. They work with any supplier’s report, not only ours, and nothing you type is sent anywhere — it is all computed in your browser.

What has to be on the report

If any of these is missing, the report has left a question unanswered. That is not proof of anything wrong, but it is a reasonable thing to ask about before paying.

• The laboratory’s name, and a way to open the report at the laboratory rather than only as a PDF from the seller.
• A lot number that matches the vial, character for character.
• A date. A report years older than the stock on sale is describing different material.
• Purity as a figure, with the method — normally HPLC — and ideally the chromatogram, not just a summary line.
• Content in milligrams per vial, which is the figure the first calculator above uses.
• Observed and expected mass as numbers. “Identity: confirmed” with no figures is an assertion, not a result.
• Net peptide content, where it was determined — this is what separates peptide from salt and water.
• Endotoxin as a number with units, if any endotoxin claim is being made at all.

Things that should stop you

• The lot number on the report does not match the vial, or the report has no lot number.
• The only copy of the report comes from the seller, and the laboratory has no record you can open yourself.
• A purity figure with no method, or a “99%+” badge with no report behind it at all.
• One report presented as covering several different lots.
• Figures on the product page that do not match the figures on the report.
• Font, alignment or number formatting that changes within one document — the usual sign of an edited PDF.

Checking a report with the laboratory

A genuine third-party report normally carries its own verification address, printed on the report itself, pointing at the laboratory’s domain. Open it there. A verification link has a per-report identifier in it, so it cannot be guessed from the report number alone — which is exactly why it is worth using: the seller cannot produce the laboratory’s copy, only the laboratory can.

What you are comparing is not whether the page loads, but whether the laboratory’s copy says the same compound, the same lot, the same date and the same figures as the document you were sent.

Our own lots are listed with their report numbers and verification links on the lab results page, so you can see what this looks like in practice before you need it. For the detail behind each check: reading a certificate of analysis, net peptide content, reading an HPLC result, and spotting a fabricated certificate.

All products referenced on this site are supplied for laboratory research use only, and are not for human or veterinary use.