PDF guideAPI Testing
API Testing — 250 Interview Questions & Answers
250 interview questions and answers on API testing — HTTP and REST fundamentals, contract validation, authentication, negative testing, Postman, automation, performance and API security — with practical examples and scenarios.
- Questions
- 250 with answers
- Topic areas
- 25
- Level
- All levels — beginner to advanced
- Edition
- First Edition • October 2026
₹399
What's inside
25 topic areas, 10 questions each.
- 01API Testing Foundations
- 02HTTP and REST Fundamentals
- 03Request Inputs and Serialization
- 04Response and Contract Validation
- 05Authentication and Authorization
- 06Negative and Boundary Testing
- 07CRUD and Business Workflows
- 08REST Design and Versioning
- 09SOAP, XML and GraphQL
- 10Postman and API Client Tools
- 11Automation Framework Design
- 12Performance and Load Testing
- 13API Security and OWASP Risks
- 14Microservices and Integration
- 15Environments, Data and CI/CD
- 16Debugging and Defect Management
- 17Advanced Reliability and Design
- 18Practical Design Exercises
- 19HTTP Error Semantics Deep Dive
- 20Data Integrity and Recovery
- 21Localization and Client Compatibility
- 22Governance and Interview Practice
- 23API Architecture and Reliability
- 24API Security Test Scenarios
- 25API Test Automation Patterns
Sample questions
Excerpts from this guide's answers.
- Q13. Explain GET, POST, PUT, PATCH and DELETE.
- GET retrieves; POST commonly creates or triggers processing; PUT replaces a representation; PATCH partially updates; DELETE requests removal. Confirm actual behavior against the contract.
- Q41. Authentication vs authorization?
- Authentication establishes identity; authorization determines permitted actions and resources. Test them separately.