The API Challenges

A learning environment to experiment, explore, and play with API Testing and Tooling

Welcome to The API Challenges.

We provide:

Video Welcome

About the Application

This is a functional API for managing A public To-Do list.

The API has documentation available.

A set of Challenges are available to guide you through the exploration and learning of the API. To complete each challenge you will have to explore a different aspect of API testing.

You can also view the data in the application without using the API. Using the Entities Explorer view.


We recommend that you use an API GUI to interact with the API e.g.


This application has been deployed to a cloud instance. It is also available to download and run locally.

When run in a cloud environment:

In single user mode, you can use the API without needing any extra headers or configuration.

Full download details are available from

How to Play in Multi-user Mode

More information on how to play the challenges in multi-user mode i.e. can be found on the multi-user instructions page:


The Challenges can be completed by issuing HTTP API requests.

e.g. GET http://localhost:4567/todos would complete the challenge to "GET the list of todos"

You can also GET http://localhost:4567/challenges to get the list of challenges and their status as an API call.

Note: you would use the url for the server that the application is running on.


Recommended books for learning about API Testing are:

More Information


This application is sponsored by - a blog and free online training and books for Software Testing and Development.

For a full list of sponsors and how you can sponsor and support this application check out our sponsorship page