20 Software Testing Interview Questions with Answers

What Are Software Testing Interview Questions?

Software testing interview questions are designed to evaluate a candidate's understanding of testing methodologies, tools, processes, and problem-solving capabilities. These questions often cover:

• Fundamental testing concepts such as verification and validation
• Manual and automated testing tools (e.g., Selenium, JIRA, TestNG)
• Bug reporting and tracking procedures
• Test case development and execution
• Knowledge of software development life cycles (SDLC/STLC)
• Scenario-based and behavioural testing questions

These questions help gauge not just the theoretical knowledge of a candidate but also their hands-on experience and critical thinking in identifying and resolving bugs in real-world environments.

Software Testing Interview Questions with Answers

Here are the top 20 software testing interview questions along with detailed sample answers to assess a candidate’s proficiency and logical approach.

1. What is the difference between Verification and Validation?

Answer: Verification checks whether the product is built correctly by assessing design documents, code, and requirements. It’s a static process. Validation evaluates whether the right product is built by testing it against user requirements. It’s a dynamic process.

2. What distinguishes sanity testing from smoke testing?

Answer:

• After a build is released, smoke testing is a preliminary test to verify fundamental functionality.
• Sanity Testing checks specific modules or functionalities after minor changes to ensure new issues are not introduced.
• Sanity is narrow and deep, whereas smoke is broad and shallow.

3. What are the different levels of software testing?

Answer:

• Unit Testing: Testing individual units/modules
• Integration Testing: Testing combined units
• System Testing: Testing the entire system end-to-end
• Acceptance Testing: Validating software from a user/business perspective

These levels are aligned with the software development lifecycle and ensure complete quality assurance.

4. What is Regression Testing?

Answer: Regression testing ensures that recent code changes haven’t affected existing functionality. It is usually automated and runs frequently during development to detect new bugs in existing features.

5. What is a Test Case?

Answer: A test case is a set of steps, conditions, and expected outcomes used to validate whether a feature or function of an application is working as intended.

6. What’s the difference between a Bug, Defect, and Error?

Answer:

• Error: Mistake made by a developer
• Defect: Difference between expected and actual results found during testing
• Bug: Phrase frequently used when the development team accepts a problem

7. What are the key elements of a test plan?

Answer:

• Scope of testing
• Objectives
• Testing strategy
• Test deliverables
• Resource allocation
• Schedule and deadlines
• Exit and entry criteria

Well-defined test plans support smoother coordination and transparency within project management software.

8. What is boundary value testing?

Answer: Boundary Value Testing focuses on testing the values at the edges of input domains. For example, if valid inputs range from 1 to 100, you test values like 0, 1, 100, and 101.

9. How do you log and track bugs?

Answer: Bugs are usually logged in tools like JIRA, Bugzilla, or TestRail. Each entry includes a description, steps to reproduce, severity, priority, screenshots, and status updates.

You can also track issues using Qandle’s task and workflow management tools to improve visibility and accountability in QA processes.

10. What is automation testing?

Answer: Software tools are used in automation testing to carry out test cases. It speeds up the testing process, improves accuracy, and is especially effective for regression and load testing. Tools include Selenium, QTP, TestNG, and JUnit.

11. What are some common automation testing tools?

Answer:

• Selenium: Open-source web application testing
• Appium: Mobile app testing
• JUnit/TestNG: Unit testing frameworks
• Postman: API testing
• Cypress: Frontend testing for modern applications

12. What is STLC?

Answer: The Software Testing Life Cycle (STLC) is a sequence of activities performed during the testing process. It includes:

• Requirement analysis
• Test planning
• Test case design
• Test environment setup
• Test execution
• Test cycle closure

13. What’s the difference between Manual Testing and Automated Testing?

Answer: Manual testing is appropriate for exploratory and usability testing and requires human labor. Automated testing uses scripts and tools, ideal for repetitive and large-scale regression tests.

14. How do you prioritize test cases?

Answer: Test cases are prioritised based on:

• Criticality of functionality
• Business impact
• Likelihood of failure
• User-facing visibility

This ensures critical modules are tested early and thoroughly.

15. What is a Traceability Matrix?

Answer: It is a document that links requirements and test cases. It helps with requirement traceability and compliance by guaranteeing that all functionalities are covered and validated.

16. How do you test a login feature?

Answer: I test both positive and negative scenarios:

• Correct username/password
• Invalid inputs (wrong credentials, empty fields)
• Session timeouts
• Password complexity checks
• Brute-force attempts

This covers functional, security, and usability aspects.

17. What is exploratory testing?

Answer: Exploratory testing includes concurrent learning, test design, and execution. It is useful for discovering unexpected issues and understanding real user behaviour.

18. What’s the difference between Severity and Priority?

Answer:

• Severity: Impact of the defect on functionality
• Priority: Urgency of fixing the defect

Example: A broken login button (High severity & high priority); typo on homepage (Low severity, possibly high priority).

19. How do you write effective bug reports?

Answer: I include:

• A clear title
• Steps to reproduce
• Actual vs expected results
• Screenshots or logs
• Device/environment details

This guarantees that developers can promptly reproduce and resolve the problem.

20. What challenges have you faced in testing?

Answer: One challenge was unclear requirements leading to missed test scenarios. I resolved this by maintaining constant communication with stakeholders and creating a test traceability matrix to ensure full coverage.

Interviewing a software tester goes beyond evaluating their ability to write test cases. It requires an in-depth understanding of their logical reasoning, attention to detail, familiarity with testing tools, and communication abilities. These software testing interview questions offer a structured way to measure both technical competence and cultural alignment.

When hiring for QA roles, pair these questions with other job-specific queries from Qandle’s HR toolkit library to build a comprehensive and standardised interview process.

Discover how to use Qandle's intelligent HR tools to manage hiring, performance reviews, and attendance monitoring all from a single, user-friendly platform.