Webservices API Testing with Postman - Complete Guide

Looking for a comprehensive and free API testing course to jumpstart your career in quality assurance? The Webservices API Testing with Postman - Complete Guide, taught by expert instructor Tigran Ter-Karapetyants, is a professional training program available on Udemy that empowers students to learn API testing online. Updated August 2026, this course provides a deep dive into the essential tools and methodologies required to validate RESTful web services, making it an ideal choice for those seeking a structured udemy course to master the technicalities of backend testing and earn a certification.

What You'll Learn

• Master Postman basics to efficiently manage API requests, collections, and environment variables for streamlined testing.
• Understand API basics and the underlying architecture that allows different software applications to communicate seamlessly.
• Implement REST API testing strategies to ensure that representational state transfer services are functioning according to specifications.
• Analyze RESTful Web Services by validating their endpoints and ensuring data integrity across various network calls.
• Apply HTTP methods such as GET, POST, PUT, and DELETE to perform a comprehensive range of CRUD operations on server resources.
• Interpret HTTP status codes to accurately identify whether an API request resulted in success, client-side errors, or server-side failures.
• Create and validate JSON schemas to ensure that the responses returned by the API match the expected data structure and types.
• Build real-world API testing workflows from simple single-request validations to complex, multi-step integration test suites.

Course Details

• Instructor: Tigran Ter-Karapetyants
• Rating: 4.6 stars
• Level: Beginner
• Language: English
• Certificate: Yes, upon completion
• Includes: Lifetime access, mobile-friendly content, and supportive online community

What This Course Covers

Foundations of API and Postman

• Introduction to the Postman interface and workspace management
• Understanding the role of APIs in modern software architecture
• Setting up the Postman environment for first-time users
• Navigating collections and folders to organize testing assets
• Basics of sending your first API request and analyzing the output

REST Architecture and Web Services

• Deep dive into Representational State Transfer (REST) principles
• Distinguishing between SOAP and RESTful web services
• Understanding statelessness and its importance in API design
• Exploring how RESTful services handle resources via URIs
• Analyzing the request-response cycle in a client-server model

Mastering the HTTP Protocol

• Comprehensive guide to HTTP methods including GET for retrieval
• Using POST methods to create new resources on the server
• Utilizing PUT and PATCH for updating existing data
• implementing DELETE methods for resource removal
• Detailed breakdown of 2xx (Success), 4xx (Client Error), and 5xx (Server Error) status codes

Data Validation and JSON Schemas

• Understanding JSON (JavaScript Object Notation) as the primary data exchange format
• How to read and write structured JSON payloads
• Implementing JSON schema validation to ensure response consistency
• Testing for data types, required fields, and array lengths in responses
• Using Postman to validate complex nested JSON objects

Practical API Testing Execution

• Designing test cases for positive and negative API scenarios
• Automating simple tests within the Postman "Tests" tab
• Creating dynamic workflows using environment and global variables
• Validating response times and performance benchmarks
• Best practices for documenting APIs for team collaboration

Who Should Take This Course

• Aspiring Test Engineers who want to transition from manual UI testing to specialized API testing roles.
• Beginner Developers seeking a practical understanding of how to test the endpoints they build using Postman.
• Computer Science Students who need a hands-on tutorial to supplement their theoretical knowledge of web services.
• QA Analysts looking to expand their toolkit by mastering RESTful API validation and JSON schema testing.
• IT Professionals transitioning into cloud or DevOps roles where API connectivity is a core component of the infrastructure.

Prerequisites

• No prior experience in API testing is needed — this course is completely beginner-friendly.
• A basic understanding of how the internet works (browsers, servers, and URLs) is recommended but not required.
• A computer with an internet connection to install the Postman desktop application.

Why Enroll in This Course

Enrolling in this program is a strategic move for anyone looking to enter the high-demand field of software quality assurance. API testing is a critical skill in the current job market, as almost every modern application relies on a network of interconnected services. Because this course is occasionally available via a free coupon for a limited time, learners can access professional-grade training at 100% off, removing the financial barrier to entry. This course stands out by combining theoretical API concepts with immediate practical application, ensuring that students don't just watch videos but actually build a testing portfolio.

Course Highlights

• Lifetime Access: Once enrolled, students have permanent access to all video lectures and updated materials.
• Self-Paced Learning: The on-demand format allows learners to progress through the API modules at their own speed.
• Industry-Standard Tooling: Focuses exclusively on Postman, the most widely used API client in the tech industry.
• Certificate of Completion: Provides a verifiable certificate that can be added to LinkedIn profiles to attract recruiters.
• Practical Approach: Emphasis on hands-on exercises and real-world projects over purely theoretical slides.
• Mobile Compatibility: Course content is optimized for mobile devices, allowing for learning on the go.

Frequently Asked Questions

Q: Is this course really free? A: This course is offered for free when a valid limited-time coupon is applied during checkout on Udemy. While Udemy courses typically have a cost, these promotional offers allow new students to access the full curriculum and certification at no cost.

Q: What will I learn in this API testing course? A: You will learn the complete lifecycle of API testing, starting from the absolute basics of HTTP and REST. The course covers how to use Postman to send requests, validate responses using JSON schemas, and handle various HTTP status codes to ensure a web service is functioning correctly.

Q: Do I get a certificate after completing this course? A: Yes, upon finishing all the video lessons and requirements, Udemy provides a certificate of completion. This document serves as proof of your proficiency in Webservices API Testing with Postman and can be shared with potential employers.

Q: Is this course suitable for beginners? A: Absolutely. The curriculum is designed specifically for those with zero prior experience in API testing. It starts with "Postman Basics" and "API Basics," gradually building up to more complex topics like JSON schema validation and workflow automation.

Q: How long do I have to enroll for free? A: Free coupons for Udemy courses are typically time-sensitive and have a limited number of redemptions. It is highly recommended to enroll as soon as the coupon is available to ensure you secure your lifetime access before the promotion expires.

Final Thoughts

The Webservices API Testing with Postman - Complete Guide is an essential resource for anyone aiming to master the art of backend validation. By bridging the gap between basic HTTP concepts and professional API testing workflows, Tigran Ter-Karapetyants provides a clear pathway for students to become competitive Test Engineers. Whether you are a complete novice or a developer looking to sharpen your QA skills, this course offers the tools and knowledge necessary to succeed in the modern software ecosystem. Start your learning journey today and master the power of Postman.