Hands-On Introduction to API Testing with Postman

Name: Hands-On Introduction to API Testing with Postman
Rating: 4.7 (44 reviews)

Learn how to test and explore REST APIs using Postman through practical, real-world examples

Created byLukasz Kallas

Last updated 5/2026

English

English [Auto],

What you'll learn

Understand what Postman is and why it’s used in real projects
Send GET, POST, PUT, and DELETE requests to REST APIs
Work with request headers, parameters, and JSON bodies
Handle authentication using tokens
Use environments and variables effectively
Organize requests using Postman collections
Write basic tests for API responses
Use pre-request scripts and dynamic data
Run collections and review test results

Course content

3 sections • 19 lectures • 1h 47m total length

Welcome!1:09
Learn API testing with Postman through hands-on demos, covering requests, headers, bodies, authentication, environments, variables, and simple tests directly in the tool.
Join Our Community0:04
What is & why Postman1:53
Learn how Postman lets you send API requests, inspect responses, and test scenarios for development, consumption by frontend, and understanding API behavior using headers, bodies, authentication, collections, and history.
Setting up Test API6:50
Set up a test API using node and express, install npm dependencies in vscode, run index.js to launch the demo API at localhost:3000, and prepare for postman testing.
Installing Postman3:37
Install the Postman desktop app or use the web version with optional sign-in, then explore history, collections, and request tabs and the basics of parameters, authorization, headers, and body.

Running our First Request4:42
Send your first request with Postman using the get method to http localhost 3000 for demo API, and view the 200 json response with a 14 ms timing and headers.
HTTP Overview/Refresher5:46
Explore HTTP basics and REST concepts, learn common methods (GET, POST, PUT, PATCH, DELETE), headers, bodies, and status codes, then test endpoints with a real API in Postman.
First POST Request4:00
Master your first real API calls in Postman by registering a user with a POST to localhost 3000/register, then log in to obtain a token for protected endpoints like /todos.
Authorization4:30
Demonstrate bearer token authentication in Postman to access protected endpoints, verify 200 with a valid token and 401 with an invalid one, and observe an empty todos array until creation.
Full CRUD5:57
Practice the full crud workflow on a todo API using Postman, including creating, reading, updating, and deleting todos with bearer authorization.
Environment & Variables9:03
Create and use environments and variables in Postman to streamline API testing, including a local base URL and a token variable for authorized requests.
Collections8:34
Create a todo API collection in Postman and save authentication and todos requests, organizing register, login, and todo operations while using environment variables for base URLs and tokens.
Automation7:14
Automate token management in Postman by using a post response script to save response.token to the environment, enabling bearer token authentication across requests.
Tests15:34
Write and run Postman tests to automatically verify API responses for the todos API, including status codes, response structure, and creating todos, via post response scripts.
Dynamic Data8:32
Use Postman's pre-request scripts to generate dynamic todo data, save IDs in environment variables, and prepare the collection runner to execute create, update, and delete without hard-coded values.
Collection Runner9:58
Use the Postman collection runner to execute fetch, post, put, delete, and register/login flows in order, and review response details, tests, and exported and shared collections.
Sharing7:23
Export and share Postman collections as JSON, import them later, and collaborate in real time, while managing environments with secure vault values for reliable API testing.

Requirements

Basic understanding of how web applications work
No prior experience with Postman required
Node.js installed (to run the provided demo API)

Description

Postman is one of the most commonly used tools when working with REST APIs. It is used by developers to explore, test, and understand APIs during development, integration, and testing.

In this course, you will learn how to use Postman through hands-on examples and a real demo API. There are no slides and no unnecessary theory — everything is done directly in Postman, step by step.

We start with a short introduction to REST concepts and the demo application that will be used throughout the course. From there, you will learn how to send requests, work with headers and request bodies, and understand API responses. We then move on to authentication, variables, environments, and organizing requests using collections.

As the course progresses, you will add tests, use pre-request scripts, and run entire collections to verify API behavior. You will also learn how to export and share collections, which is commonly done in real projects.

The course follows the same structure as my other hands-on introductions. Each topic is introduced only when it becomes useful, and every concept is shown in practice. The goal is to help you understand not only how Postman works, but how it fits into everyday development and testing workflows.

This course is beginner-friendly and designed to be a practical introduction to API testing with Postman.

Who this course is for:

Beginner developers learning to work with APIs
Frontend developers who want to understand backend APIs better
Backend developers who want a simple API testing workflow
Anyone who wants a practical introduction to Postman

Hands-On Introduction to API Testing with Postman

What you'll learn

Explore related topics

Course content

Welcome & Setup5 lectures • 14min

Postman Basics12 lectures • 1hr 31min

Ending2 lectures • 3min

Requirements

Description

Who this course is for: