The Vendor Transparency Standard
Last revised
20 criteria for judging what a peptide seller will tell you, and what they leave out. We name no vendors and rank none. The criteria are published so you can apply them without us.
Why a standard, and not a list.
The usual advice for buying research peptides is to find a seller other people trust. That advice fails for a simple reason: the people recommending are rarely the people testing, and a reputation built in a comment section carries no documentation behind it. Ask which batch was tested, by whom, and against what method, and most recommendations have no answer.
This standard scores what a seller discloses. It does not score product quality, and it cannot. Nobody can assess a vial from a website. A seller who publishes batch-matched independent testing might still ship poor material; a seller who publishes nothing might ship excellent material. What disclosure tells you is whether you are in a position to find out, and whether the seller has arranged things so you can check their claims or so you cannot.
Most criteria can be answered from public information, a product page or a single email, before you pay. That is deliberate. A standard you can only apply after purchase comes too late. Two criteria need the vial in hand: the lot number on the certificate, and the lot number printed on the vial.
We publish criteria rather than a ranked list of sellers for two reasons. A list goes stale the week after it is published, because a supplier that documented well last quarter can change laboratories, change contract manufacturers, or quietly stop publishing. And the moment anyone ranks sellers, someone starts paying to move up the ranking. Criteria cannot be bought.
What the 20 criteria cover.
Five sections, in the order they disqualify fastest. Testing rigor comes first, because without a batch-matched certificate the remaining sixteen criteria are academic.
Testing rigor
A certificate of analysis is only evidence if it describes the vial you were sent. That means a matching lot number, a named laboratory with no stake in the result, and a stated method rather than the word tested.
HPLC and mass spectrometry reporting
Purity and identity are different questions and need different instruments. HPLC tells you how much of the contents is the main component; mass spectrometry tells you whether that component is the peptide on the label.
Batch traceability
Documentation that cannot be tied to a specific batch is decoration. Lot numbers belong on the vial, past certificates should stay retrievable, and one generic document reused across every batch proves nothing at all.
Regulatory compliance and claims
How a seller talks about a product is evidence in itself. Dosing guidance, implied health outcomes, or a claimed approval that does not exist all tell you the seller has decided which rules apply to them.
Operational transparency
Who you are dealing with should be checkable before you pay. A registered identity, a disclosed manufacturing country, a real route for documentation requests, and stated cold-chain handling where the product needs it.
Apply it to a real seller.
The checklist tool walks all 20 criteria one at a time and scores as you go. Nothing you enter leaves your browser.
Open the seller checklistWhat a score does not mean.
A high score is not an endorsement and a low score is not an accusation. Small operations serving genuine laboratories often score poorly on operational transparency while running careful chemistry, because their customers are institutions who ask for documents directly rather than expecting to read them on a website.
Read which criteria failed rather than how many. Four gaps in operational transparency describe a seller who is hard to identify. Four gaps in testing rigor describe a seller whose product is unverified. Those are different problems and only one of them is about chemistry.
And a seller who passes every criterion has proven only that they document their work. They have not proven the compound does anything. That question is answered by trial data, not by paperwork, and it is what the compound table tracks: how many completed randomized human trials exist for each compound, and where each sits with regulators.
What this standard is not
It is not an endorsement scheme, a certification, or a buying guide. Meeting every criterion says a seller documents its product well. It does not make an unapproved compound safe, legal, or appropriate for human use, and nothing here is medical advice.
Ask better questions.
The standard is revised when testing practice or regulation changes. Revisions go out in the Wednesday email, with what changed and why.