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Testing + certificates

What is a certificate of analysis (COA)?

⚡ Short answer

A certificate of analysis is a lab report for one specific batch. For peptides it should confirm identity (usually by mass spectrometry) and purity (usually by HPLC), and carry the batch number, test date and the lab's name.

Educational onlyUpdated 21 Oct 2026
Testing + certificates

One batch, one report

A COA describes the material from a single production batch. A certificate for a different batch, or one with no batch number at all, tells you nothing about the vial in front of you.

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What a peptide COA should contain

The product name and the batch or lot number.
Identity: the measured mass compared with the expected mass.
Purity: an HPLC result, ideally with the chromatogram itself.
Quantity: the amount of material measured per vial.
The lab's name, test date and a way to verify the report.
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In-house or third-party?

An in-house COA is written by the seller's own lab. A third-party COA comes from an independent lab with no stake in the result. Many independent labs let you check a report on their website using a code printed on it.

Educational information only

Educational information only. Nothing here is medical advice, dosing guidance or a recommendation to use any substance. Research peptides are not approved medicines and are not for human or animal consumption. Speak to a qualified professional and follow the law where you are.

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