The COA Verifier is a small desk tool with one job: you pick the laboratory that issued a certificate of analysis, paste in the report or accession code, and it hands you the link to check that code at the lab's own website. It does not verify anything by itself — it runs no assays, queries no databases, and makes no judgment about whether a certificate is genuine. It just saves you the hunt for the right portal.
Where the lab's verify link pattern is documented, the tool builds the full URL directly. Where a lab runs a public portal but the exact query format hasn't been established, it opens that portal with your code ready to paste. Where a lab has no public lookup at all — portal login or direct contact only — the tool says so instead of pretending. If the link comes back empty, the usual causes are an aged-out certificate, a mistyped code, or a number the lab never issued; the page walks through what to do in each case. Readers without any code can't verify, and the supplier evaluation checklist explains why a supplier who won't provide one is a signal worth noting.
The labs covered here are the same ones on the testing labs list, and every one of them appears because documented suppliers name them on certificates. The tool carries no scores and no endorsements. Check supplier profiles on the Supplier Desk, read how to read a certificate of analysis, and report broken links or unverifiable codes on the contact page. Our independence rules live in Editorial Standards.