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Panorama Open Scholarly Index

How certificates work

A certificate of indexing states that specific publications are indexed in the Panorama Open Scholarly Index, and whether each one appeared in a Core Collection journal. Issue one here. It is free and immediate.

What POSI indexes

POSI indexes every journal with DOIs registered at Crossref or DataCite, or a source record in OpenAlex. Each DOI is checked at the agency that registered it, as named by doi.org. A publication is indexed when Crossref holds its DOI as a journal article under a journal ISSN; when DataCite, or Zenodo for a Zenodo DOI, holds it as a journal article that is part of a journal with an ISSN; or, failing those, when OpenAlex records it with a journal as its source. Books, chapters, datasets and preprints are not journal publications and are not certified, and neither is a journal article whose record names no journal ISSN.

Google Scholar has no public API and does not allow automated queries, so it cannot be part of the check. The check results link each publication to a Google Scholar search, so you can confirm it is listed there by hand.

Within the index, journals that applied for certification and passed the PQF editorial evaluation form the Core Collection. The certificate names each publication's journal status: Core Collection or Indexed.

What the certificate contains

  • A certificate number, the date of issue and the data snapshot the check ran against.
  • The requester, affiliation and purpose, exactly as typed by the person issuing it. These are not verified.
  • For each indexed publication: title, authors, journal, volume, issue, pages, year, DOI, ISSN, the registry it was indexed through, an accession number, the journal status and the registry citation count on the date of issue.
  • A QR code and address for verification.

Up to 20 DOIs can be checked at once. DOIs that are not indexed are counted but not listed. Certificates are issued in English.

How the numbers are made

The certificate number (PC-XXXX-XXXX-XXXX) is the first 12 hexadecimal digits of SHA-256 over POSI-CERT-2|date of issue|snapshot|DOIs, with DOIs lower-cased and sorted. The accession number (POSI-A-XXXXX-XXXXX) is the first 10 hexadecimal digits of SHA-256 over the lower-cased DOI, so a publication keeps the same accession number whatever happens to its journal. Both are deterministic and can be recomputed by anyone; the code is in src/lib/certificate.ts.

How verification works

Verification does not depend on a register of issued certificates. It re-derives each certificate from its contents:

  • The certificate number is recomputed from the date, snapshot and DOI list in the link. A mismatch means the certificate was altered.
  • Every DOI is re-checked against Crossref, DataCite, Zenodo, OpenAlex and the current POSI index. Changes since issue, such as a journal leaving the Core Collection, are reported.

Because the facts are checked again every time, a certificate claiming a publication is indexed when it is not fails verification, whoever produced it. Printed names and purposes are not part of the link and are not verified; relying parties should confirm identity separately.

Zone certificates

A zone certificate (POSI 分区证书) states a journal's POSI Zone in the current Citation Ranking: the zone of its PNCI percentile within its PSC subject category (Zone 1: top 5%; Zone 2: top 5–20%; Zone 3: top 20–50%; Zone 4: lower 50%). It is available for every journal with an official zone (an official ranking in a category of at least 50 ranked journals), from the journal's profile page, and needs no application.

  • The category, the zone, the citation rank, category size, percentile and Citation Quartile.
  • The journal's title, publisher, ISSNs and POSI ID, its PNCI, and the ranking snapshot, data snapshot and zone rule (POSI-ZONES-2.0) it was read from.

The certificate number (PZ-XXXX-XXXX-XXXX) is the first 12 hexadecimal digits of SHA-256 over POSI-ZONE-CERT-2|zone rule|date of issue|POSI ID|edition year|category|zone. Verification recomputes it from the journal's current ranking record. Ranks are deliberately left out, so a certificate stays valid while its zone holds and stops verifying when the zone changes or the edition year moves on, with the next annual edition each December. The code is in src/lib/zone-certificate.ts.

Certificates issued before 28 September 2026 stated zones of the retired PCS-based trial (POSI-ZONES-1.0, POSI-ZONE-CERT-1). That ranking has been withdrawn, so they no longer verify.

Appropriate use

A certificate records indexing status or ranking position. It is not an assessment of the quality of a publication or journal. See responsible use.