This page shows exactly how a supplier's trust grade gets calculated — the inputs, the weights, the grade scale — so it can be checked, not just trusted.
For how a supplier gets listed at all and how this site makes money, see /trust.
A supplier's score comes from four weighted inputs, built entirely from their actual Certificates of Analysis — not their marketing copy.
Batch-specific COA
Does the COA tie to a specific batch or lot — or is it one good test from years ago, recycled across every product on the site? A COA with no lot number tells you nothing about what you're actually buying. It's the single biggest factor in the score.
Named third-party lab
Was testing done by a named, independent lab whose results you can check against their own database (Janoshik Analytical is a common example here) — not an unnamed or in-house lab whose findings nobody outside the supplier can verify.
Safety panel beyond purity
Most COAs report HPLC purity and stop there. Does testing also cover heavy metals, microbial contamination, and endotoxins — the things that actually determine whether a sample is safe, not just how concentrated it is.
Direct verification
Has CompoundSearch personally confirmed something with the supplier directly — a reply, a document, a batch sent on request — rather than relying only on what they publish about themselves.
The four weighted inputs add up to a score out of 100, which maps to a letter grade:
A grade only appears once someone has sat down with a supplier's real COAs and confirmed all four inputs above. Right now that's 0 of 10 suppliers — everyone else shows "not yet reviewed" on /trust.
That label means exactly what it says: the review hasn't happened yet, not that anything is wrong. Nothing here is scored by guesswork, and no supplier can pay to skip the line.