Skip to main content
The GemRate API gives you programmatic access to graded trading-card data: look up a specific certificate, get a card’s population and its history, resolve a grader spec to a card, and download bulk catalogs.

​
Base URL

All routes live under the /v1 version prefix:
Reads are GET requests over HTTPS. The contract evolves additive-only within v1.

​
Authentication

Send your API key in the x-api-key header on every request:
  • Missing or invalid key → 401.
  • Valid key without access to a resource → 403.

​
Response envelope

Every success is { "data": …, "meta": { "request_id": … } }; lists put pagination in meta.pagination. Errors carry a stable, machine-readable code:

​
Grades & labels

Population and grade data is reported under each grader’s own label keys ({grader}_{grade}, e.g. psa_10, beckett_9_5, cgc_10_perfect).

​
Resources

Certs

A specific graded copy — GET /v1/certs/{grader}/{cert} (+ /images).

Cards

The card itself + population — GET /v1/cards/{gemrate_id} (+ /history).

Specs

A grader’s catalog entry — GET /v1/specs/{grader}/{spec_id}.

Catalogs

Bulk CSV download — GET /v1/catalogs/{catalog}.