API Practice Modes
Practice modes are the hands-on part of the site. Use them to send real requests, compare responses with expectations, and build confidence with different API behaviours.
Choose A Practice Mode
| Practice Mode | What You Will Learn |
|---|---|
| Simulation Mode | Request construction and response interpretation without changing server-side data. |
| API Challenges | A guided challenge set for learning API operations, status codes, headers, and state changes. |
| Simple API | Stateful CRUD practice with a small API that supports JSON, XML, and OpenAPI files. |
| Buggy API | How to investigate deliberately buggy behaviour in an API with more realistic business rules. |
| Mirror Mode | How to inspect exactly what your client sends by having the server mirror request details back. |
| API From Hell | How tools and tests behave around awkward API design, unusual formats, and hostile edge cases. |
OpenAPI Files
Use the OpenAPI file pages when you want to load a practice API into a client or OpenAPI UI:
- API Challenges OpenAPI files
- API Simulator OpenAPI files
- Simple API OpenAPI files
- Buggy API OpenAPI files
Suggested Flow
Start in Simulation Mode, then move to the Simple API for persistent data. Use API Challenges to practise coverage, then review the Challenge Solutions after you have attempted the scenarios yourself.