Magnitia’s Web services Testing Training will provide you complete knowledge on Web services, API and their functionality. This API Testing course enables you to develop robust automation Framework for API’s test cases and how to test Web services and REST API using SoapUI& Rest Assured.

1. Top 20 API Testing Interview Questions
& Answers in 2023
1. What is an API, and why do we need to test it?
An API (Application Programming Interface) is a set of protocols and tools for
building software applications. It enables communication and data exchange
between different software applications. We need to test APIs to ensure that they
meet the requirements and work as expected.
2. What is API testing?
API testing is a type of software testing that involves testing APIs directly without
any graphical user interface. It validates that the API meets the requirements,
functions as expected, and provides accurate responses.
3. What are the types of API testing?
The types of API testing are unit testing, functional testing, load testing, security
testing, error handling testing, and UI testing.
4. What is the difference between SOAP and REST APIs?
SOAP (Simple Object Access Protocol) is a protocol that uses XML to exchange data
between systems, while REST (Representational State Transfer) is an architectural
style that uses HTTP to exchange data between systems. REST is more lightweight,
scalable, and easier to use than SOAP.

2. 5. What is the difference between POST and GET methods?
POST is used to submit data to a server to create a new resource, while GET is used
to retrieve data from a server.
6. What is JSON?
JSON (JavaScript Object Notation) is a lightweight data interchange format that is
easy for humans to read and write and easy for machines to parse and generate.
7. What is an assertion in API testing?
An assertion in API testing is a way of verifying the expected result against the actual
result. It validates that the API response meets the expected criteria.
8. What is an endpoint in API testing?
An endpoint is a URL that is used to access a specific API resource.
9. What is a status code in API testing?
A status code is a three-digit code that indicates the status of an HTTP request. It
helps to determine whether the API request was successful or not.
10. What is a query parameter in API testing?
A query parameter is a parameter that is passed in the URL to filter and sort data.
11. What is a header in API testing?
A header is a piece of metadata that is passed in the HTTP request or response. It
provides additional information about the request or response.
12. What is a mock API?
A mock API is a simulated API that can be used to test the functionality of an API
client without relying on a real API server.
13. What is API documentation, and why is it important?
API documentation is a set of instructions that describes how to use an API. It is
important because it helps developers to understand how to use the API and ensures
that the API is used correctly.

3. 14. What is API versioning?
API versioning is the practice of creating multiple versions of an API to allow for
backward compatibility and to prevent breaking changes.
15. What is API throttling?
API throttling is the practice of limiting the number of requests that can be made to
an API within a certain period to prevent server overload.
16. What is CORS?
CORS (Cross-Origin Resource Sharing) is a security mechanism that allows restricted
resources on a web page to be requested from another domain outside the domain
from which the resource originated.
17. What is serialisation in API testing?
Serialisation is the process of converting an object into a format that can be
transmitted over a network or stored in a file.
18. What is deserialization in API testing?
Deserialization is the process of converting a serialised object back into its original
form.
19. What is the difference between positive and negative testing?
Positive testing is testing the system’s expected behaviour when provided with valid
input, while negative testing is testing the system’s behaviour when provided with
invalid input.
20. What is test coverage?
Test coverage is a measure of the degree to which the code of a software system has
been tested. It is usually expressed as a percentage, indicating the proportion of the
code that has been executed during testing. Test coverage is important because it
helps to ensure that all parts of the code are being tested and that the system is
functioning as expected. It also helps to identify areas of the code that are not being
tested adequately and may require additional testing. Test coverage can be
measured using various tools and techniques, such as code coverage analysis and
test case management systems.

4. How to Start a Career in API Testing?
If you’re interested in starting a career in API testing, Magnitia IT Training can be
a great resource to help you get started. Here are the steps you can follow to begin
your journey:
1. Learn the basics of software testing: Before you dive into API testing, it’s important to
have a good understanding of the fundamentals of software testing. Magnitia IT Training
offers a variety of courses and resources on software testing that can help you get up to
speed.
2. Learn the basics of APIs: It’s important to have a solid understanding of what APIs are, how
they work, and how they are used in software development. Magnitia IT Training offers
courses on APIs and related technologies that can help you gain this knowledge.
3. Learn API testing tools and techniques: To be an effective API tester, you’ll need to be
familiar with a variety of tools and techniques used in API testing. Magnitia IT Training offers
courses on popular API testing tools like Postman, as well as courses on API testing best
practices.
4. Practice, practice, practice: The best way to become proficient in API testing is to practice
as much as possible. Magnitia IT Training offers hands-on training and projects that allow
you to practice your skills in a real-world setting.
5. Build a portfolio: As you gain experience and skills in API testing, it’s important to build a
portfolio of your work. This can include projects you’ve worked on, test cases you’ve
developed, and any other relevant work. Magnitia IT Training can help you build a portfolio
that showcases your skills and experience.
6. Look for job opportunities: Once you feel confident in your skills and have a strong
portfolio, it’s time to start looking for job opportunities in API testing. Magnitia IT Training
offers job placement assistance and can help you find opportunities that match your skills
and experience.

5. By following these steps and taking advantage of Magnitia IT Training’s resources
and courses, you can start a successful career in API testing.