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openapi: 3.2.0
info:
title: Open Trivia DB Categories API
description: Free JSON API providing trivia questions across multiple categories, difficulties, and types. No API key is required. Supports session tokens to avoid duplicate questions across requests, multiple response encodings, and rate limiting of one request per IP every 5 seconds.
version: '1.0'
contact:
name: Open Trivia DB
url: https://opentdb.com
license:
name: Creative Commons Attribution-ShareAlike 4.0 International
url: https://creativecommons.org/licenses/by-sa/4.0/
servers:
- url: https://opentdb.com
description: Open Trivia DB Production
tags:
- name: Categories
description: Retrieve available trivia categories.
paths:
/api_category.php:
get:
tags:
- Categories
summary: List trivia categories
description: Returns all available trivia categories with IDs and names.
operationId: getCategories
responses:
'200':
description: List of categories.
content:
application/json:
schema:
$ref: '#/components/schemas/CategoriesResponse'
/api_count.php:
get:
tags:
- Categories
summary: Question count for category
description: Returns the total and remaining question counts for a category.
operationId: getCategoryCount
parameters:
- name: category
in: query
required: true
description: Category ID.
schema:
type: integer
responses:
'200':
description: Category question count.
/api_count_global.php:
get:
tags:
- Categories
summary: Global question counts
description: Returns global question counts across all categories.
operationId: getGlobalCount
responses:
'200':
description: Global counts response.
components:
schemas:
CategoriesResponse:
type: object
properties:
trivia_categories:
type: array
items:
type: object
properties:
id:
type: integer
name:
type: string
externalDocs:
description: Open Trivia DB API Documentation
url: https://opentdb.com/api_config.php