Cataas

aid: cataas
name: Cataas
description: >-
  Cataas (Cat as a Service) is a free, open-source REST API that returns
  random cat images and GIFs with optional tags, filters, sizing, and text
  overlays. The service is widely embedded in tutorials, demos, README files,
  and chat applications as a friction-free image source. The canonical
  implementation lives at github.com/cataas/cataas and runs at cataas.com.
url: https://cataas.com/
specificationVersion: '0.20'
created: '2026-05-28'
modified: '2026-05-30'
x-source: public-apis/public-apis
x-category: Animals
x-type: opensource
x-tier: 3
x-tier-reason: bulk-registered-from-public-apis
tags:
  - Animals
  - Cats
  - Images
  - Open Source
  - Public APIs
apis:
  - name: Cataas
    description: >-
      Random and tagged cat image retrieval with optional sizing, filtering,
      and text overlay. Includes a JSON catalog API and admin/upload endpoints
      for the canonical hosted instance.
    humanURL: https://cataas.com/
    baseURL: https://cataas.com
    tags:
      - Cats
      - Images
    properties:
      - type: Documentation
        url: https://cataas.com/
      - type: OpenAPI
        url: openapi/cataas-openapi-original.yml
      - type: JSONSchema
        url: json-schema/cat-schema.json
      - type: JSONSchema
        url: json-schema/count-response-schema.json
      - type: JSONSchema
        url: json-schema/upload-cat-request-schema.json
      - type: JSONSchema
        url: json-schema/edit-cat-request-schema.json
      - type: JSONStructure
        url: json-structure/cat-structure.json
      - type: JSONStructure
        url: json-structure/count-response-structure.json
      - type: JSONStructure
        url: json-structure/upload-cat-request-structure.json
      - type: JSONStructure
        url: json-structure/edit-cat-request-structure.json
      - type: Example
        url: examples/cat-example.json
      - type: Example
        url: examples/count-response-example.json
      - type: Example
        url: examples/upload-cat-request-example.json
      - type: Example
        url: examples/edit-cat-request-example.json
      - type: NaftikoCapability
        url: capabilities/cataas-cats.yaml
      - type: NaftikoCapability
        url: capabilities/cataas-catalog.yaml
      - type: NaftikoCapability
        url: capabilities/cataas-upload.yaml
      - type: NaftikoCapability
        url: capabilities/cataas-admin.yaml
      - type: SDK
        url: https://github.com/iArmanKarimi/Cataas-API-js
        title: JavaScript / TypeScript Wrapper (community)
      - type: SDK
        url: https://github.com/iArmanKarimi/Cataas-API-go
        title: Go Wrapper (community)
      - type: SDK
        url: https://github.com/chimpook/cataas-api-php
        title: PHP Wrapper (community)
common:
  - type: Website
    url: https://cataas.com/
  - type: GitHubOrganization
    url: https://github.com/cataas
  - type: GitHubRepository
    url: https://github.com/cataas/cataas
    title: Canonical Cataas server (Node.js)
  - type: GitHubRepository
    url: https://github.com/cataas/discord-bot
    title: Cataas Discord bot
  - type: GitHubRepository
    url: https://github.com/cataas/slack-command
    title: Cataas Slack slash command
  - type: GitHubRepository
    url: https://github.com/cataas/image-editor
    title: Cataas image editor library
  - type: Tools
    title: MCP Server (community via Pipeworx Gateway)
    url: https://github.com/pipeworx-io/mcp-cataas
  - type: PublicAPIsListing
    url: https://github.com/public-apis/public-apis
  - type: SpectralRules
    url: rules/cataas-spectral-rules.yml
  - type: Vocabulary
    url: vocabulary/cataas-vocabulary.yaml
  - type: JSON-LD
    url: json-ld/cataas-context.jsonld
  - type: Features
    data:
      - name: Random Cat Image
        description: GET /cat returns a random cat image (JPEG, PNG, or GIF).
      - name: Tagged Cat Retrieval
        description: GET /cat/{tag} returns a random cat matching one or more comma-separated tags.
      - name: Animated GIFs
        description: GET /cat/gif returns a random animated cat.
      - name: Text Overlay
        description: GET /cat/says/{text} renders user-supplied text on top of a random cat with configurable font size, color, and background.
      - name: Image Filters
        description: filter=blur|mono|negate|custom with per-channel and per-property tuning (brightness, hue, saturation, RGB).
      - name: Sizing and Cropping
        description: type, width, height, fit, and position query parameters resize and crop the returned image.
      - name: JSON Catalog API
        description: /api/cats, /api/tags, /api/count expose the catalog programmatically.
      - name: Content Negotiation
        description: json=true returns a metadata document instead of binary; html=true returns an embedding wrapper page.
      - name: Free and Unauthenticated
        description: All read endpoints are public and require no API key.
  - type: UseCases
    data:
      - name: Tutorials and Demos
        description: Embed live cat images in API tutorials, learn-to-code lessons, and conference demos.
      - name: README Decoration
        description: Decorate open-source READMEs and personal sites with rotating cat imagery.
      - name: Chat Bots and Slash Commands
        description: Slack, Discord, and Teams bots fetch random cats on demand via /cat or /cat/says.
      - name: Mocking Image-Heavy APIs
        description: Stand in for a real image-CDN-backed API while prototyping front-end layouts.
      - name: Image Pipeline Testing
        description: Exercise resize, format-conversion, and filtering pipelines with predictable image input.
  - type: Integrations
    data:
      - name: Slack
        description: Official slack-command repo wires /cat into Slack workspaces.
      - name: Discord
        description: Official discord-bot repo provides a Cataas Discord integration.
      - name: Pipeworx MCP Gateway
        description: Community MCP server (pipeworx-io/mcp-cataas) wraps the API for use by Claude and other MCP clients.
      - name: Public APIs Catalog
        description: Listed in the public-apis/public-apis Animals category.
  - type: Solutions
    data:
      - name: Self-Hosted Catalog
        description: Run your own Cataas instance from cataas/cataas (Node.js + MongoDB + sharp) to power internal demos or branded image services.
maintainers:
  - FN: Kin Lane
    email: kin@apievangelist.com