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OpenAlex API

Free OpenAlex API with no key: 250M+ scholarly works, authors, institutions, topics and citation graph. The open replacement for Microsoft Academic. Tested.

No API key requiredCORS enabledHTTPSFree tier

Endpoint tested and returned HTTP 200 on 20 Aug 2026

What is the OpenAlex API?

OpenAlex is a free, key-free API cataloguing more than 250 million scholarly works along with authors, institutions, sources, topics and the citation graph connecting them — an open replacement for the discontinued Microsoft Academic Graph.

OpenAlex goes beyond bibliographic records to model the whole scholarly ecosystem as linked entities: works cite works, authors belong to institutions, works have topics. That graph structure is what makes it useful for research analytics rather than simple lookup.

Its group-by aggregation is genuinely powerful — you can ask for counts of works grouped by publication year, institution or open-access status in one request, which would otherwise require paging through millions of records.

Quick facts

Base URL
https://api.openalex.org
Authentication
No API key. Adding `mailto=` joins the faster polite pool, as with Crossref.
Rate limit
100,000 requests per day and 10 per second, which is generous.
Pricing
Free and fully open — the entire dataset is also downloadable.
CORS
Enabled — callable directly from browser JavaScript
Official docs
Read the docs

How to use the OpenAlex API

Every request below was executed against the live API on 20 Aug 2026, and the response shown is the real body it returned — not an illustration.

1. Query scholarly works

GET https://api.openalex.org/works?per-page=1

curl
curl 'https://api.openalex.org/works?per-page=1'
JavaScript (fetch)
const res = await fetch("https://api.openalex.org/works?per-page=1");
if (!res.ok) throw new Error(`Request failed: ${res.status}`);
const data = await res.json();
console.log(data);
Python (requests)
import requests

res = requests.get("https://api.openalex.org/works?per-page=1", timeout=20)
res.raise_for_status()
print(res.json())
Response — HTTP 200 (truncated)
{
  "meta": {
    "count": 322044938,
    "db_response_time_ms": 150,
    "page": 1,
    "per_page": 1,
    "groups_count": null,
    "x_query": {
      "oql": "works",
      "oqo": {
        "get_rows": "works"
      },
      "url": "/works?per_page=1"
    },
    "cost_usd": 0.0001
  },
  "results": [
    {
      "id": "https://openalex.org/W3038568908",
      "doi": "https://doi.org/10.1585/pfr.15.2402039",
      "title": "Radiation Resistant Camera System for Monitoring Deuterium Plasma Discharges in the Large Helical Device",
      "display_name": "Radiation Resistant Camera System for Monitoring Deuterium Plasma Discharges in the Large Helical Device",
      "publication_year": 2020,
      "publication_date": "2020-06-08",
      "ids": {
        "openalex": "https://openalex.org/W3038568908",
        "doi": "https://doi.org/10.1585/pfr.15.2402039",
        "mag": "3038568908"
      },
      "language": "en",
      "primary_location": {
        "id": "doi:10.1585/pfr.15.2402039",
        "is_oa": true,
        "landing_page_url": "https://doi.org/10.1585/pfr.15.2402039",
        "pdf_url": "https://www.jstage.jst.go.jp/article/pfr/15/0/15_2402039/_pdf",
        "source": {
          "id": "https://openalex.org/S46033839",
          "display_name": "Plasma and Fusion Research",
          "issn_l": "1880-6821",
          "issn": [
            "1880-6821"
          ],
          "is_oa": true,
          "is_in_doaj": false,
          "is_core": true,
          "host_organization": "https://openalex.org/P4328135220",
          "host_organization_name": "Japan Society of Plas

Parameters

ParameterTypeRequiredDescription
per-pageintegerOptionalResults per page, max 200. 25
page / cursorstringOptionalPagination; cursor for deep paging. *
searchstringOptionalFull-text search across works. climate change
filterstringOptionalFilters such as publication_year or is_oa. publication_year:2026
group_bystringOptionalAggregate counts by a field instead of listing works. publication_year
mailtostringOptionalYour email, for the polite pool. you@example.com

Response fields

meta.countinteger
Total works matching the query.
results[].idstring
OpenAlex entity URL, the canonical identifier.
results[].doistring
DOI where one exists.
results[].titlestring
Work title as a plain string, unlike Crossref.
results[].authorshipsarray
Authors with institution affiliations.
results[].cited_by_countinteger
Citation count.
results[].open_accessobject
Open access status and best available URL.
results[].topicsarray
Classified research topics with confidence scores.

What you can build with the OpenAlex API

  • Build research analytics and bibliometric dashboards
  • Analyse institutional publication output and collaboration
  • Find open-access versions of paywalled papers
  • Map research topics and citation networks

Common errors and how to fix them

403 or throttling

Anonymous pool under load.

Fix: Add mailto= to join the polite pool; it is free and noticeably more reliable.

Deep paging fails

Page-based paging is capped.

Fix: Use cursor=* and follow meta.next_cursor for large result sets.

Filter syntax errors

Filters use colon-separated field:value pairs joined by commas.

Fix: For example filter=publication_year:2026,is_oa:true.

OpenAlex API — frequently asked questions

Is OpenAlex free?

Yes, completely free and open with no API key, at 100,000 requests per day. The entire dataset is also available as a downloadable snapshot.

How is it different from Crossref?

Crossref is authoritative for DOI metadata. OpenAlex models the wider scholarly graph — authors, institutions, topics and citations as linked entities — which suits analytics rather than pure lookup.

What replaced Microsoft Academic Graph?

OpenAlex was built explicitly as its open successor after Microsoft discontinued MAG in 2021.

Can I aggregate without downloading everything?

Yes, group_by returns counts grouped by a field such as publication_year or institution in a single request — a major advantage over paging.

Tools that pair with this API

Alternatives to OpenAlex API

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OpenAlex is an independent third-party service and is not affiliated with ByteTools or ByteVancer. Details on this page were verified on 20 Aug 2026; always check the official documentation before relying on this API in production, as terms and limits can change.