---
title: "List concepts (deprecated)"
method: GET
path: "/concepts"
tags: ["Concepts"]
deprecated: true
---

# List concepts (deprecated)

`GET /concepts`

> **Deprecated.**

**DEPRECATED:** Use Topics instead. Get a list of concepts from the legacy taxonomy.

## Query parameters

- `filter` string
- `sort` string
- `group_by` string
- `search` string
- `per_page` integer
- `page` integer
- `cursor` string
- `sample` integer
- `select` string
- `api_key` string, required

## Response `200`

Successful response

- ConceptsListResponse
  - `meta` Meta — Metadata about the query results
    - `count` integer — Total number of results matching the query
    - `db_response_time_ms` integer — Database response time in milliseconds
    - `page` integer — Current page number
    - `per_page` integer — Number of results per page
    - `next_cursor` string — Cursor for the next page (when using cursor pagination)
    - `groups_count` integer, nullable — Number of groups when using group_by
    - `cost_usd` number — Cost of this request in USD
  - `results` Concept[]
    - `id` string — The OpenAlex ID for this concept.
    - `display_name` string — The name of the concept.
    - `description` string — A description of this concept.
    - `level` integer — The hierarchical level (0 = top level, higher = more specific).
    - `wikidata` string — The Wikidata ID for this concept.
    - `ids` object — External identifiers:
      - `openalex` string
      - `wikidata` string
      - `wikipedia` string
      - `mag` integer, nullable
    - `image_url` string, nullable — URL for an image representing this concept.
    - `image_thumbnail_url` string, nullable — Smaller version of `image_url`.
    - `works_count` integer — The number of works tagged with this concept.
    - `cited_by_count` integer — Total citations to works tagged with this concept.
    - `ancestors` unknown[], nullable — Parent concepts in the hierarchy.
      - unknown
    - `related_concepts` unknown[], nullable — Related concepts with similarity scores.
      - unknown
    - `counts_by_year` unknown[], nullable — `works_count` and `cited_by_count` for each of the last ten years.
      - unknown
    - `works_api_url` string — A URL that returns all works tagged with this concept.
    - `created_date` string, date — When this concept was added to OpenAlex (ISO 8601 date).
    - `updated_date` string, date-time — When this concept was last updated (ISO 8601 datetime).

## Other responses

- `400` — Bad request - invalid parameters
- `429` — Rate limit exceeded

---

[API](https://skmtc.net/openalex/apis/openalex-api.md) · [All operations](https://skmtc.net/openalex/apis/openalex-api/llms.txt) · [OpenAPI document](https://skmtc-service-staging.skmtc.workers.dev/v1/apis/openalex/openalex-api/revisions/60b6c8bd0799/schema)