How to use the checklist
Open the certificate for the exact lot on your vial, not a generic product COA. Work through the four groups: does it match your vial, can you trace and verify the lab, do the results cover purity, identity and content, and are there signs the PDF was edited. Each unchecked item is a question to put to the vendor.
For a line-by-line walkthrough of each field, read how to read a peptide COA. For the purity number specifically, see HPLC purity explained, and for Janoshik certificates, how to verify a Janoshik report.
See how vendors compare
Our vendor testing tracker shows which of our listed vendors name a lab, publish lot-level certificates and have independent test data.
Frequently asked questions
What should a peptide COA include?
The compound name, a lot or batch number that matches your vial, the test date, the named lab, purity by HPLC with a chromatogram, identity by mass spectrometry and, ideally, measured content in mg.
How do I know if a COA is real?
Verify it with the lab that issued it, using the lab's lookup tool, QR code, accession code or email. A certificate you can't trace to a named lab can't be verified.
Is high HPLC purity enough?
No. HPLC purity shows the share of the main peak, not that the peak is the right compound or how much is in the vial. Identity needs mass spectrometry, and quantity needs a content result.
More free tools
- Peptide reconstitution calculator (U-100 and U-40)
- BAC water calculator
- Peptide unit converter (mg, mcg, IU, mL and units)
- COA checklist
- Vendor testing tracker
Choosing a supplier? See the best peptide vendors in the USA.