API Study Guide 2026
Everything you need to pass the API exam in one place: the exam format, every topic to study, real practice questions with explanations, flashcards, and full-length practice tests. Free, no sign-up needed.
📋 API Exam Format at a Glance
📚 API Topics to Study (35)
✍️ Sample API Questions & Answers
1. What is the purpose of the 'record and replay' feature found in API mocking tools?
Record and replay captures live HTTP traffic from a real API and uses those recordings as mock responses, ensuring that mock data is realistic and matches actual API behavior.
2. Which HTTP header is used to send a Bearer token in API requests?
Bearer tokens are sent in the Authorization header using the format 'Authorization: Bearer '.
3. What is a GraphQL 'schema' used for?
The GraphQL schema is the contract that defines every type, field, query, mutation, and subscription the API exposes.
4. Which HTTP status code means 'No Content' after a successful DELETE?
204 No Content is commonly returned after a successful DELETE when there is no body to return.
5. What does the Apdex score measure in API performance monitoring?
Apdex (Application Performance Index) is a standardized score from 0–1 measuring user satisfaction by bucketing response times into Satisfied, Tolerating, and Frustrated.
6. Which Python library is commonly used for writing automated REST API tests?
The `requests` library handles HTTP calls while `pytest` provides the test framework, making them the standard Python combo for API test automation.