Score a seller before you buy.
Open the seller's documentation in another tab and work down the list. Tick only what you have actually seen, because a promise to send a document is not the document. Nothing you enter here leaves your browser: progress is saved only in this browser, so you can switch tabs and come back.
Printable edition: one sheet per seller, free with your email address.
- 0 to 9
- 10 to 15
- 16 to 20
Score 0 of 20
Your ticks and this reference are saved only in this browser. Reset clears both.
Testing rigor
Whether the seller proves what is in the vial, by batch, with methods you can check.
HPLC and mass spectrometry reporting
Purity and identity are two separate questions, each needing its own method.
Batch traceability
Documentation is only meaningful when it can be tied to a specific batch.
Regulatory compliance and claims
How a seller talks about its product is itself evidence.
Operational transparency
Basic verifiable facts about who you are dealing with.
Reading your score
Before anything else, look at which criteria failed rather than how many. Four gaps in operational transparency is a very different seller from four gaps in testing rigor.
Claims can be verified against documents. You are able to audit this seller, which is the most any buyer can ask of a website.
Some documentation exists, with gaps. Identify which criteria failed and ask about those specifically before deciding.
You are relying on the seller's word. That may be fine. It is a different decision from the one a scored seller offers you.
A high score is not an endorsement and a low score is not an accusation. The score describes the information available to you, and nothing beyond it.
Take it with you.
The tool above scores in your browser and saves your progress only in this browser. The printable edition is a five-page PDF: one sheet per seller, with write-in boxes, the scoring bands, and the guidance on how to read a result. It is free, and the download opens here as soon as you sign up.
- All 20 criteria laid out to print and tick by hand
- Scoring bands and how to interpret a failed section
- The Wednesday email too, which you can leave on the first click
Educational only. Not an endorsement, not a certification, not medical advice.