JSON Quiz Test Online (30 random Questions) 2025

This quick 30-minute challenge consists of 30 random multiple-choice questions designed to test your knowledge across various JSON topics, including the introduction to JSON, JSON syntax and basics, data types, operations in JavaScript, APIs and JSON, advanced structures, JSON Schema, tools and debugging, as well as performance and security considerations. Whether you’re new to JSON or looking to refine your skills, this quiz will enhance your understanding of JSON’s role in modern web development.

0 votes, 0 avg

You have 30 minutes to complete the quiz. The timer will start when you click the 'Start Quiz' button. Please ensure you are ready before beginning.

Time is up! Your quiz has ended. Your responses have been submitted automatically.

30 Minutes JSON Quiz Test Online

Welcome to the JSON Quiz! This quick 30-minute challenge consists of 30 random multiple-choice questions designed to test your knowledge across various JSON topics, including the introduction to JSON, JSON syntax and basics, data types, operations in JavaScript, APIs and JSON, advanced structures, JSON Schema, tools and debugging, as well as performance and security considerations. Whether you're new to JSON or looking to refine your skills, this quiz will enhance your understanding of JSON's role in modern web development.

1 / 30

1. Which messaging protocol often uses JSON for message payloads?

A) SMTP

B) FTP

C) MQTT

D) POP3

2 / 30

2. Can JSON arrays contain objects?

A) Yes

B) No

C) Only strings

D) Only numbers

3 / 30

3. What is the purpose of the Authorization header in API requests?

A) To specify the API version

B) To include authentication credentials

C) To set request priority

D) To specify data format

4 / 30

4. What does a JSON path debugger do?

A) Converts JSON to CSV

B) Extracts specific values from JSON

C) Validates JSON syntax

D) Beautifies JSON

5 / 30

5. Can JSON objects be nested inside other JSON objects?

A) No

B) Only with arrays

C) Yes

D) Only with strings

6 / 30

6. Which of the following values is not valid in JSON?

A) 123

B) "Hello"

C) undefined

D) null

7 / 30

7. What will JSON.stringify(true) return?

A) "True"

B) Throws an error

C) "true"

D) true

8 / 30

8. Which JavaScript function converts JSON data into a format suitable for POST requests?

A) JSON.encode()

B) JSON.parse()

C) JSON.compress()

D) JSON.stringify()

9 / 30

9. What is the effect of caching JSON responses?

A) Converts JSON to binary format

B) Prevents JSON injection attacks

C) Increases JSON size

D) Reduces server processing time for repeated requests

10 / 30

10. What does the oneOf keyword do in JSON Schema?

A) Ensures that the data matches exactly one of the specified schemas

B) Combines multiple schemas

C) Requires all listed schemas to match

D) Validates against one specific type

11 / 30

11. How do you specify a format for email validation in JSON Schema?

A) format: "email"

B) pattern: "/[email]/"

C) validate: "email"

D) type: "email"

12 / 30

12. What happens if a JSON object has circular references when using JSON.stringify()?

A) It converts successfully

B) It throws a TypeError

C) It skips the circular reference and continues

D) It returns an empty object

13 / 30

13. What is the root element of a JSON document?

A) A string

B) A number

C) A key-value pair

D) An object or array

14 / 30

14. How is JSON used in microservices architecture?

A) To define database schemas

B) To render UI components

C) To compile service code

D) To exchange data between microservices

15 / 30

15. Which of the following JSON values is equivalent to "no value"?

A) undefined

B) ""

C) none

D) null

16 / 30

16. What error does a missing comma between JSON key-value pairs produce?

A) Undefined object

B) Invalid JSON

C) SyntaxError: Unexpected token

D) Missing property name

17 / 30

17. Which of the following is used to validate the syntax of JSON data?

A) JSON Formatter

B) JSON Compressor

C) JSON Beautifier

D) JSON Validator

18 / 30

18. What does the Accept header specify in an API request?

A) The authentication type

B) The client type

C) The data format expected in the response

D) The server's API version

19 / 30

19. How do you access the value "Alice" from the JSON object {"name": "Alice", "age": 25}?

A) object[1]

B) object["Alice"]

C) object[0]

D) object.name

20 / 30

20. Can a JSON key have a number as its name?

A) Only in arrays

B) Yes, without quotes

C) No

D) Yes, with quotes

21 / 30

21. What is a common use of JSON in analytics platforms?

A) Storing raw event data

B) Defining UI components

C) Generating static reports

D) Compiling JavaScript files

22 / 30

22. Which of the following files often uses JSON for configuration?

A) config.txt

B) config.xml

C) settings.json

D) preferences.ini

23 / 30

23. Can a JSON object have duplicate keys?

A) Only in arrays

B) No

C) Only in nested objects

D) Yes

24 / 30

24. What is the MIME type for JSON?

A) text/json

B) application/json

C) text/plain

D) application/javascript

25 / 30

25. How do you specify a pattern for a string in JSON Schema?

A) pattern

B) match

C) format

D) regex

26 / 30

26. How does HTTPS improve the security of JSON data transmission?

A) It makes JSON larger

B) It validates JSON schemas

C) It beautifies JSON responses

D) It encrypts JSON data in transit

27 / 30

27. How are floating-point numbers represented in JSON?

A) "1.23"

B) 1.23

C) float(1.23)

D) 1.23f

28 / 30

28. Which keyword in JSON Schema defines the type of a value?

A) format

B) type

C) properties

D) items

29 / 30

29. What is the advantage of using JSON in IoT (Internet of Things) devices?

A) It is faster than wireless communication

B) It provides a lightweight and flexible data format

C) It reduces power consumption

D) It encrypts all data automatically

30 / 30

30. What is the purpose of JSON in REST APIs?

A) To structure and exchange data between client and server

B) To define API endpoints

C) To render HTML pages

D) To validate API responses

Your score is

The average score is 40%

Rate Your Experience!

Anonymous feedback

Thank you for your feedback! We appreciate your input.

Online Quiz Test (with time limit)

HTML Quiz Test Online

Bootstrap Quiz Test Online (30 random Questions)

10 Minutes JavaScript Quiz Test Online

CSS Quiz Test Online (30 random Questions)

MongoDB Quiz Test Online (30 random Questions)

Related