Where these compounds actually come from, why two vials with the same label can test differently, and how to check the one you bought instead of trusting a recommendation.
A grey market peptide is a compound sold lawfully as a research chemical, by a vendor who makes no medical claim, to a buyer who very often intends to use it themselves. It is not a black market — nothing is counterfeit by definition, and most sellers are not hiding.
What makes it grey is the missing middle. In the pharmaceutical chain, someone between the factory and you is legally answerable for every batch: identity, purity, sterility, what the label says. In this market that link is simply absent. Nobody upstream is checking on your behalf, and no regulator will notice if a run comes out wrong.
That is the whole problem, and it is a narrower problem than the panic around it suggests. It isn't that these compounds are usually bad. It's that nothing systematically catches the ones that are.
The single most common way people choose a vendor is to read that someone else was happy with theirs. That is evidence about a different vial than the one you will receive.
Read that third number carefully, because it cuts against the scare stories as much as it cuts against the vendor loyalty. The overwhelming majority of what gets tested is fine. The risk here is not a coin flip — it is a tail. And a tail is exactly the thing a recommendation cannot protect you from, because the person recommending their vendor almost certainly did not get a tail vial either.
Across 1,025 retatrutide tests from 196 shops, one shop's 24 results run from 64.1% to 100% purity — a 35.9 point range from one seller. Most of their batches are fine. One was not.
We aren't naming them, because the point isn't that this shop is bad — it is that "is this shop good?" is the wrong question. The right one is "what did this batch test at?"
Each production run is its own event: its own synthesis, purification, handling and storage. A vendor's reputation is an average over runs you will never receive. A certificate tied to your lot number is evidence about the vial in your hand.
Headline vial prices are close to meaningless on their own. A cheaper vial containing less than its label says is not cheaper, and two vials at the same price can differ several-fold in what you actually get per milligram once concentration and dose are worked through.
We deliberately publish no price list. Prices move constantly, and a stale number presented as current is worse than no number. What we publish instead is the arithmetic, so you can run it against whatever you are actually being quoted today:
A vial's real cost is price ÷ (tested milligrams × tested purity). Anything else is a sticker.
Retatrutide is the compound this market is most preoccupied with right now, and it is the clearest illustration of the whole problem: it is still in clinical trials, which means there is no approved product, no pharmacy supply, and no official batch anywhere to compare against. Every vial in circulation is a research-chemical vial.
It is also, for the same reason, the most-tested compound in our library — 1,025 third-party results, which is the only substitute available for a supply chain nobody is auditing.
This site cannot tell you where to buy anything, and does not try to. What it can do is turn "who should I trust?" into a question with an answer.
Peptigrity does not sell, supply, source, or recommend any compound, and nothing on this page is medical or legal advice. We index third-party lab results and we take no money from vendors.