API Testing resources
39 API Testing resources are available in the QA Vault right now. They cover fundamentals, http methods, status codes, requests & responses and authentication. That is roughly 975 pages of notes, all readable online and downloadable with Vault access.
REST, HTTP and API automation notes.
Fundamentals
10 resources in api testing.
API Testing: Complete Notes (Updated)
13-page API testing notes: HTTP methods and idempotency, status codes and errors, risk-based test design, validation beyond the body, auth and security, pagination, CRUD and async jobs, Postman and Playwright.
13 pages · PDF
API Testing Essentials: Complete Notes
13-page API testing notes: HTTP methods and idempotency, status codes and headers, risk-based test design, validation beyond the body, auth and security, pagination, CRUD and async jobs, Postman assertions and Playwright API tests.
13 pages · PDF
API Testing Beyond 200 OK: Complete Notes
13-page notes on API testing beyond 200 OK: status codes and headers, schema and meaning, business rules, state changes, authorization, bad inputs, retries and races, lists and pagination, speed and failure behaviour.
13 pages · PDF
Payment API Testing Scenarios: Complete Notes
13-page practical notes on payment API testing: payment states, amount and currency checks, access rules, success and decline, 3D Secure, idempotency, timeouts, webhooks, capture, refunds and reconciliation.
13 pages · PDF
200 API Testing Interview Questions & Detailed Answers
200 API testing interview questions with detailed answers, arranged across eight interview areas from API fundamentals to real-world project scenarios.
35 pages · PDF
JSON Complete Notes for API Testers
This PDF serves as a complete guide for API testers, explaining JSON syntax, data types, and schemas.
17 pages · PDF
REST Assured Complete Notes
REST Assured Complete Notes — notes for QA engineers, 22 pages.
22 pages · PDF
API Authentication Complete Notes
API Authentication Complete Notes — notes for QA engineers, 22 pages.
22 pages · PDF
API Testing Roadmap: Beginner to Expert
API Testing Roadmap: Beginner to Expert — roadmap for QA engineers, 22 pages.
22 pages · PDF
API Testing Complete Notes — Beginner to Advanced
This PDF provides complete notes on API testing, guiding readers from beginner concepts to advanced topics.
45 pages · PDF
HTTP Methods
3 resources in api testing.
API Testing: 30 Interview Questions and Answers
A study guide containing 30 API testing interview questions and answers covering HTTP methods, schema validation, authorization, and test design.
13 pages · PDF
GET vs POST vs PUT vs PATCH vs DELETE
GET vs POST vs PUT vs PATCH vs DELETE — career guide for QA engineers, 22 pages.
22 pages · PDF
HTTP Methods Complete Guide
This guide provides a practical handbook for understanding and testing HTTP methods in REST APIs.
20 pages · PDF
Status Codes
3 resources in api testing.
HTTP Status Codes: Interview Guide
A 13-page interview guide covering start with the meaning, then test the outcome, 200 ok, 201 created, 204 no content.
13 pages · PDF
API Validation Complete Cheat Sheet
10-slide cheat sheet on what to validate in an API response: status codes, headers, JSON schema, values, invalid inputs, access control, pagination and a Playwright example.
10 pages · PDF
HTTP Status Codes Every Tester Must Know
HTTP Status Codes Every Tester Must Know — career guide for QA engineers, 22 pages.
22 pages · PDF
Requests & Responses
7 resources in api testing.
API Playground: Hands-On API Practice Guide
A 13-page guide covering a practice space built for testers, send your first request, understand what you send, practise the full data journey.
13 pages · PDF
API Pagination Testing Cheat Sheet
10-slide cheat sheet on testing paginated APIs: page boundaries, metadata, gaps and duplicates, stable sorting and filters, negative inputs and data changing between requests.
10 pages · PDF
JSONPath Cheat Sheet for API Testers
10-slide JSONPath cheat sheet with one sample JSON: array indexes, dot vs bracket notation, filters, slices, deep search, missing vs null and turning queries into tests.
10 pages · PDF
Query Params vs Path Params Cheat Sheet
10-slide visual cheat sheet on the difference between path and query parameters, with test checklists, encoding rules and interview answers.
10 pages · PDF
API and Database Validation Practical Guide
This guide provides a hands-on approach to validating API requests, responses, and data persistence directly against the database.
34 pages · PDF
Headers vs Query Params vs Path Params — Complete Guide for API Testers
Where request data belongs, how path params, query params and headers behave, and how to test each one, with test cases, security checks, automation code and interview prep.
20 pages · PDF
API Request & Response Complete Guide
This guide covers how API requests are structured, how responses are interpreted, and methods for testing both.
20 pages · PDF
Authentication
2 resources in api testing.
OAuth 2.0 Complete Guide for Testers
Grant types, tokens and flows explained the tester's way, with test cases, security attack scenarios, automation code and interview prep.
31 pages · PDF
JWT Authentication Testing Complete Guide
Token anatomy, validation rules and attack scenarios explained the tester's way, with test cases, automation code and interview prep.
21 pages · PDF
Assertions & Validation
1 resource in api testing.
Postman
1 resource in api testing.
Test Cases & Scenarios
3 resources in api testing.
100 Negative API Test Cases Every QA Should Know
This guide details 100 negative API test cases across 11 categories, structured to help QA, SDET, and API testers prove an API cannot be broken, bypassed, or abused.
17 pages · PDF
API Test Cases Every QA Should Know
API Test Cases Every QA Should Know — test cases for QA engineers, 22 pages.
22 pages · PDF
API Testing Real-Time Interview Scenarios
API Testing Real-Time Interview Scenarios — career guide for QA engineers, 22 pages.
22 pages · PDF
Automation & Frameworks
3 resources in api testing.
REST Assured Complete Practical Guide
REST Assured Complete Practical Guide — practical API Testing notes for software testers, 109 pages.
109 pages · PDF
API Automation Framework From Scratch With REST Assured
API Automation Framework From Scratch With REST Assured — practical api testing notes for software testers, 34 pages.
34 pages · PDF
API Automation Framework From Scratch
API Automation Framework From Scratch — career guide for QA engineers, 22 pages.
22 pages · PDF
Interview Questions
3 resources in api testing.
100 API Testing Interview Questions
100 API Testing Interview Questions — interview questions for QA engineers, 22 pages.
22 pages · PDF
50 API Testing Interview Questions
50 API Testing Interview Questions — interview questions for QA engineers, 22 pages.
22 pages · PDF
API Testing Interview Questions
API Testing Interview Questions — interview questions for QA engineers, 22 pages.
22 pages · PDF
Roadmaps & Learning Paths
1 resource in api testing.
Career, Resume & Salary
1 resource in api testing.
More resources
1 resource in api testing.
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API Testing Fundamentals for Beginners
8 beginner lessons in about 45 minutes: what an API is, HTTP methods and status codes, JSON, your first requests in Postman, authentication, negative testing and a mini project on a real practice API.
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39 API Testing resources are included with QA Vault access.