Free guide 02

Judge a supplier on evidence, not on reviews.

Ten pages on working out whether a supplier is worth your money: a scorecard you apply yourself, how to read a certificate of analysis, and the failure patterns that show up again and again.

It contains no vendor list and no rankings. We have no laboratory, so we cannot tell you what is in a vial. What we can do is teach you the 6 checks, which is why this will still be accurate next year when a ranked list would not be.

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What is inside

  • The 6 point scorecard, as a form you fill in per supplier. Works on names that did not exist when it was written.
  • How to read a certificate of analysis, and why net peptide content matters more than the purity figure everyone quotes.
  • How to verify a certificate with the issuing lab instead of taking the seller’s PDF at face value.
  • The full red flag table with severities, separating walk-away signals from proceed-carefully ones.
  • Payment methods ranked by what recourse you actually have when something goes wrong.
  • What to check the moment a parcel arrives, before you open anything.

These are the same criteria we score our own listings against on the suppliers page, where the score is computed from published evidence and the commercial relationship is a field the scoring function never reads.

Not medical advice, and not legal advice about what you may buy, import or possess. Those rules vary by jurisdiction and change often.