Purity claims are cheap to make and hard to verify. This page sets out what each vendor actually documents, whether the laboratory doing the work is named, and what a Certificate of Analysis can and cannot tell you.
Most disputes about peptide quality come down to confusing two separate questions. A certificate can answer both, one, or neither.
How clean is it. Reported as a percentage of total peak area. A figure is method-dependent: two labs using different columns or wavelengths can differ by 1–3% on identical material, so the stated method matters as much as the number.
Is it the right molecule. Compares observed mass against the theoretical mass for the sequence. A compound can be 99.5% pure and still be entirely the wrong peptide — purity alone cannot catch that.
How much is in the vial. Distinct from purity, which says nothing about fill weight. This is the figure that matters when a label says 10 mg and the vial holds less.
What else is in there. Contaminants that neither purity nor identity testing will reveal. Commonly the first tests omitted when a panel is abbreviated.
Drawn from each vendor's own published material. Where a column reads "not stated", that means the vendor does not say — not that the testing did not happen.
| Vendor | Standing | Purity | Identity | Contaminants | Lab named | COAs public |
|---|
The grouping is not about who claims the highest purity — nearly everyone claims 99%. It is about whether an outside party could confirm the claim.
Separate from vendor quality. These follow the molecule regardless of who sells it, and appear on the relevant listings as well.
Every numbered claim above links here. Regulatory status and molecular data come from the issuing body or a public chemical database; the enforcement account comes from mainstream news reporting; the Melanotan II content figures come from a peer-reviewed analytical study.
Testing information is taken from each vendor's own website and, where noted, from independent third-party trackers. It reflects what could be confirmed on the date shown against each vendor and is not itself laboratory verification. Vendors change practices; a claim confirmed once is not a permanent guarantee. Nothing here is an endorsement, and a higher grouping is not a recommendation to buy.
Research use only — nothing on this site is intended for human or animal consumption.