← The courseModule 01: Before you buy
9 min read · free lesson

The vendor landscape

Who actually makes this stuff, who resells it, and why the same vial costs $30 from one site and $90 from another.

Very few peptide vendors make peptides. The synthesis happens at a small number of contract manufacturers, most of them in China, and everyone downstream is buying bulk powder, having it filled into vials, and putting a label on it. The brand you see is a label and a website. What matters is what is behind it.

The four kinds of seller

Why prices vary so much

Bulk peptide is cheap. A vial that retails for $60 can carry a few dollars of actual compound. The price difference between vendors is testing, filling standards, insurance against the payment processor shutting them down, and margin. A very low price is usually a drop-ship brand skipping the first two. A very high one is often a brand rather than a better product.

The useful question is never what does it cost. It is what did they test, who tested it, and can I see it. The next lesson is how to read the answer.

This course does not recommend vendors and never will. A recommendation is a sale by another name, and the lesson would be out of date the week a supplier changed. What you get instead is the checklist that lets you judge any of them yourself.
The legal reality, in plain termsReading a certificate of analysis
The vendor landscape — Before you buy — The Peptide Course | Peptide Reference Guide