COA Format Specification (v1)
Every Certificate of Analysis we issue conforms to the format described below. This page is the authoritative spec — versioned, stable, and meant to be programmatically parseable by retailers, marketplace brand-registry teams, and aggregators that need to verify a GSA COA without a human-in-the-loop step.
Identifier scheme
Every COA carries a unique accession number in the format:
GSA-YYYY-NNNNNN
where YYYY is the calendar year of submission and NNNNNN is a zero-padded six-digit sequence number. Example: GSA-2026-018901. Accession numbers are monotonic within a year and never reused. Six digits are the minimum width; the suffix may grow to seven if annual volume exceeds 999,999 lots.
Verification
The canonical lookup URL is:
https://www.goldstandardanalytics.com/coa-lookup?accession={accession}
https://www.goldstandardanalytics.com/coa-lookup?accession={accession}&key={key}Public COAs resolve from the first URL. Private COAs require the second; the key is the verification key the customer received in their portal. Both URLs are stable and will continue to resolve correctly forever — old accession numbers are never recycled.
Programmatic API
For machine integrations, hit the JSON endpoint:
GET /api/coa/lookup?accession={accession}[&verificationKey={key}]
-> 200 { ok: true, found: true, coa: {...} }
-> 200 { ok: true, found: false }
-> 429 { ok: false, error: "Too many lookups. Please slow down." }The endpoint is rate-limited to 60 requests/minute/IP. High-volume integrators should contact us for an API key with raised limits.
Required fields on every COA
- accession_number — the canonical identifier (above)
- compound — what was tested
- lot_number — the customer-supplied lot identifier
- matrix — sample form (powder, oil, capsule, soil, water, etc.)
- methods — analytical methods cited by reference (USP <X>, EPA <X>, etc.)
- results[] — pass/fail rows with label, value, spec, status
- issued_at — date the COA was signed
- received_at — date the sample arrived at our lab
- status — one of
draft,reviewing,published,retracted
Versioning policy
Breaking changes to the COA format (renaming a field, changing a field's shape or semantics) bump the major version and get a new spec page (/legal/coa-spec-v2 etc.). Additive changes (new optional fields) keep the same major version. The public lookup will always serve every previously-issued COA in its original format.
Retraction
A COA can be marked retracted by Gold Standard if the underlying instrument data is later found to be invalid (rare, but we will reach out and replace it). A retracted COA still resolves but the lookup response will surface the retraction status.
Contact
Programmatic-integration questions: team@goldstandardanalytics.com.