REST API Tutorial Path

By Alan RichardsonUpdated 2026-08-14

This path gives you a practical order for learning REST API testing. It starts with making requests, adds the HTTP and REST vocabulary you need, then moves into OpenAPI, test design, practice environments, and worked solution review.

Use it as the main route through the Learning Zone. Each step links to a page on the site and explains what that page is for, what you should practise there, and why it prepares you for the next step.

The Path

Interactive REST API Tutorial

This is the hands-on starting point. You send real requests from the browser, inspect responses, use headers, and learn the API Challenges endpoints without needing to install a REST client first.

Use it to get comfortable with the mechanics of requests and responses before moving into the reference material.
HTTP Basics

This is the reference page for the protocol details behind the requests you just sent. It explains request and response structure, headers, bodies, status lines, and the parts of HTTP that your API client is showing you.

Use it when you want to understand the raw evidence in an API exchange.
REST API Basics

This page explains the REST style: resources, representations, CRUD operations, statelessness, and the conventions that make REST APIs predictable enough to explore and test.

Use it to connect HTTP requests to API design ideas such as resources, state changes, and representations.
HTTP Methods

This reference page explains what GET, POST, PUT, PATCH, DELETE, HEAD, OPTIONS, and QUERY are expected to do.

Use it to decide which method fits a test idea, and to recognise when an API behaves unexpectedly for a method.
HTTP Status Codes

This section of the HTTP Basics page explains the meaning of success, client error, server error, redirect, and edge-case responses.

Use it to turn a response code into a useful testing observation rather than just treating it as pass or fail.
OpenAPI

This reference page explains how OpenAPI files describe endpoints, schemas, operations, examples, and tool-friendly API contracts.

Use it to learn how documentation and generated clients can help you find requests to try, payloads to vary, and assumptions to challenge.
Interactive How to Test REST APIs Tutorial

This tutorial moves from making requests into designing API tests. It shows how to vary inputs, check state, review headers, and think about useful coverage.

Use it when you are ready to make your API work more deliberate and evidence-driven.
Interactive API Simulation

This walkthrough uses the simulator to practise request and response handling in a controlled environment.

Use it to experiment safely before moving into APIs that persist data, track challenge progress, or require more careful cleanup.
API Challenges

This is the main challenge application. You work through tracked challenges, create and update data, inspect outcomes, and practise real API testing decisions.

Use it to apply the concepts from the tutorials and reference pages in a more active, goal-oriented way.
Challenge Solutions

These pages are worked examples for the challenges. They explain request setup, expected status codes, payload details, hints, and lessons learned.

Use them after you try a challenge so you can compare your reasoning with a guided solution and improve your own testing approach.
Simple API Experiments

This page turns Simple API into an exploratory test plan. It suggests experiments for CRUD, validation, state checks, content negotiation, request body formats, error responses, documentation comparison, and automation candidates.

Use it when you want to move from guided challenge completion into broader test coverage thinking.

How To Use The Path

Move through the list in order the first time. After that, treat it as a map: jump back to HTTP, REST, or OpenAPI when a challenge exposes a gap, then return to the hands-on pages and keep testing.