JSONPlaceholder

Free fake REST API for testing and prototyping

JSONPlaceholder is a free online REST API that provides fake data for prototyping and testing. It offers six resources — posts, comments, albums, photos, todos, and users — with full CRUD support (GET, POST, PUT, PATCH, DELETE). Responses are realistic JSON data that mimics a social platform. For OpenClaw agents, JSONPlaceholder is perfect for testing and prototyping skills that interact with REST APIs. When building a new skill, you can develop your HTTP request logic against JSONPlaceholder before switching to the real API. It's also useful for demos and tutorials where you need a reliable, always-available API.

Tags: utility, development

Category: Development

Use Cases

  • Prototype REST API skills before connecting to real data sources
  • Test OpenClaw's HTTP handling without risking rate limits on real APIs
  • Build demo workflows that showcase agent capabilities with reliable data

Tips

  • Use the /posts?_limit=5 parameter to test pagination handling
  • Combine resources with nested routes like /posts/1/comments for relationship testing
  • Great for building OpenClaw skill templates that others can customize for real APIs

Known Issues & Gotchas

  • Write operations (POST/PUT/DELETE) are faked — data is not actually persisted
  • Only 6 resource types available — may not cover complex testing scenarios
  • All data is in English — not suitable for testing localization

Frequently Asked Questions

Does JSONPlaceholder actually save data on POST/PUT/DELETE?

No. Write operations are simulated — the server returns the expected response but doesn't persist changes. GET requests always return the same seed data.

Is JSONPlaceholder reliable for automated testing?

Yes, it has excellent uptime and consistent responses. It's widely used in CI/CD pipelines and tutorials. The data never changes, making it ideal for deterministic tests.

Are there alternatives with more complex data?

Yes. ReqRes.in offers user-focused fake data with pagination. DummyJSON provides 10+ resource types. For custom schemas, Mocky.io lets you define your own responses.