A WireMock alternative for practice, not for stubbing a contract

WireMock is a mature HTTP mock server — a Java library, a standalone process and a Docker image — built for stubbing third-party APIs in automated tests. Stubs match requests on method, URL, headers and body, and return the responses you define; it can record real traffic and replay it, inject faults such as delays and dropped connections, and simulate stateful scenarios.

At a glance

Where it stops

Every response it gives is one you wrote. That is its strength when you need to reproduce a specific contract inside CI, and the limit when the goal is to learn or rehearse: the API cannot surprise you, its rules are as complete as your stubs, and setting it up for anything beyond a handful of endpoints is real engineering work.

What is different here

This playground is the opposite trade. There is nothing to define, and the behaviour — conflicts, version checks, rate limits, async jobs, token expiry — follows rules you did not write, the way a real third-party API does. It is a place to practise and to learn what to stub, not a replacement for stubbing your own dependencies in CI.

What WireMock does better

• Reproduces one specific third-party contract exactly, including undocumented quirks you have observed.
• Runs inside your test process or CI with no external dependency.
• Record-and-playback captures a real API's responses as stubs.
• Fine-grained fault injection: delays, malformed responses, connection resets.
• Request verification: assert that your code called the dependency the way it should.

What this playground does better

• Zero setup — no stubs, JVM, container or configuration.
• A wide, ready-made surface: 39 APIs with persistent state and real constraints.
• Rules written by someone else, so tests discover client behaviour rather than confirm your stubs.
• Interactive docs and generated code in nine languages for learning and demos.

Which to use

For stubbing a real dependency in your test suite, WireMock is the right tool and this is not. For learning API testing, building a practice suite or demonstrating client behaviour against realistic rules, this is ready with no setup.

Checked against WireMock as of 2026-09.

Other comparisons

• JSONPlaceholder — JSONPlaceholder fakes its writes. If you need a POST that a later GET can find, that is the difference.
• httpbin — httpbin shows you the request. This shows you an API. They answer different questions.
• reqres.in — reqres is a clean, tiny user API with fake auth. The gap is everything past the happy path.
• json-server — json-server turns a JSON file into a REST API in seconds. It does not push back — and that is the difference.
• Mockoon — Mockoon is for designing your own mock API. This one is an API already designed, with rules you have to discover.
• Beeceptor — Beeceptor gives you a hosted endpoint to inspect and mock. This gives you finished APIs that behave like real ones.
• DummyJSON — DummyJSON has rich sample data and a JWT login. Its writes are simulated; here they persist.
• Postman mock servers — A Postman mock server replays the examples saved in a collection. This one runs an API with state and rules.
• PokeAPI — PokeAPI is the real Pokémon database, read-only. This Pokémon API is invented data you can write to and break.
• SWAPI — SWAPI serves Star Wars data, read-only. This Star Wars API is invented practice data you can change.
• the free mock API landscape — Six free options, what each is genuinely for, and how to tell which one your problem needs.

All 39 mock REST APIs · Getting started guide · About this playground

Last updated 15 October 2026