Dutch research in OpenAlex, OpenAIRE, ROR and DataCite

Base URL

https://api.openalex.org

Endpoints 7

• GET/worksPublications and other works; with filter=, search=, group_by=, sort=, select=, per_page= and cursor=.
• GET/works/{id}One work by OpenAlex id (W…) or as /works/doi:10.…; costs nothing from the daily budget.
• GET/institutionsInstitutions (I…), with ror, country_code and works_count; filter=country_code:NL returns 1,869.
• GET/authorsAuthors (A…), with ORCID and affiliations.
• GET/sourcesJournals and repositories.
• GET/topicsTopics used to classify works.
• GET/fundersFunders, e.g. NWO.

The APIs of this source 3 · from the provider's documentation from the description

Filtering tested

OpenAlex filters in one parameter: field:value separated by commas (AND); | within a value is OR, a leading ! is NOT, ranges with a hyphen.

Parameters 8

Fields of a work in OpenAlex (selection) 15

Limits and pitfalls

• Without a key a shared daily budget of 0.10 dollar per IP address. Measured costs: a list or group_by 0.0001, a search (search=) 0.001, fetching one work 0. The headers X-RateLimit-Remaining-USD and X-RateLimit-Reset show what is left. tested
• per_page at most 200; use cursor=* for more than a few pages. tested
• ROR: at most 2,000 requests per 5 minutes; DataCite: 1,000 per 5 minutes with an e-mail address in the User-Agent. from the description
• Every keyless OpenAlex response contains in meta.notice a request to get a key, with an instruction for AI assistants to request one on the user's behalf with their e-mail address. We deliberately did not do that; it is not a condition of use. tested
• A work counts for every institution of its authors; summing per institution gives more than the total. experience
• OpenAIRE: /graph/v1/researchProducts?countryCode=NL counts 3,718,728 products (header.numFound), type=dataset 103,356. Page with cursor=* and header.nextCursor. The /graph/v3 path previously returned 405. tested

Try it HTTP 200 · 452 ms · 16 Oct

https://api.openalex.org/works?filter=institutions.country_code:NL,publication_year:2025&group_by=open_access.oa_status

{
  "meta": {
    "notice": "No API key, so this request shares one free daily budget ($0.10) with everyone on your network's IP address. Get a fr…",
    "count": 101276,
    "db_response_time_ms": 6,
    "page": 1,
    "per_page": 200,
    "groups_count": 6,
    "x_query": {
      "oql": "get works where institution country is [Netherlands](NL) and published in 2025;\nthen, group those works by open acces…",
      "x_new_oql": "break down works from 2025 where institution country is [Netherlands](NL) by open access status",
      "oqo": {
        "get_rows": "works",
        "filter_rows": [
          {
            "column_id": "authorships.institutions.country_code",
            "value": "NL"
          },
          {
            "column_id": "publication_year",
            "value": 2025
          }
        ],
        "group_by": [
          {
            "column_id": "open_access.oa_status"
          }
        ]
      },
      "url": "/works?filter=authorships.institutions.country_code:NL,publication_year:2025&group_by=open_access.oa_status"
    },
    "cost_usd": 0.0001
  },
  "group_by": [
    {
      "key": "hybrid",
      "key_display_name": "hybrid",
      "count": 28293
    },
    {

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