Open Library

Open Library Subjects API

Retrieve books, works, and metadata grouped by subject (genre, topic, place, time, person) with paging and faceting.

GitHub OpenAPI

Operations 1

GET /subjects/{subject}.json List works for a subject #

Documentation

📖
Documentation
https://openlibrary.org/dev/docs/api/subjects

Specifications

⚙
OpenAPI
https://raw.githubusercontent.com/api-evangelist/open-library/refs/heads/main/openapi/open-library-subjects-api-openapi.yml

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OpenAPI Specification

open-library-subjects-api-openapi.yml Raw ↑ 
openapi: 3.2.0
info:
  title: Open Library Subjects API
  description: 'Open Library''s public, read-only REST API for searching books, authors,

    and works, retrieving structured records (works, editions, authors,

    subjects), fetching cover images, and pulling recent changes. No

    authentication is required; clients are expected to send a descriptive

    `User-Agent` header to receive a higher per-second rate limit.'
  version: 1.0.0
  contact:
    name: Open Library Developer Documentation
    url: https://openlibrary.org/developers/api
servers:
- url: https://openlibrary.org
  description: Open Library production
- url: https://covers.openlibrary.org
  description: Open Library covers service
tags:
- name: Subjects
paths:
  /subjects/{subject}.json:
    get:
      summary: List works for a subject
      parameters:
      - name: subject
        in: path
        required: true
        schema:
          type: string
      responses:
        '200':
          $ref: '#/components/responses/Record'
      tags:
      - Subjects
      operationId: getSubjects{subject}Json
      x-operation-id-source: derived
components:
  responses:
    Record:
      description: Open Library JSON record.
      content:
        application/json:
          schema:
            type: object
            additionalProperties: true