1000+ QA Engineer Interview Questions and Answers

A high severity low priority bug is a software defect that has a significant impact on the system but can be deferred for a later release.

• It is a bug that affects a critical functionality of the system

• It does not require an immediate fix and can be postponed

• It may not affect the end user experience directly

• It can be fixed in a future release or patch

• Examples include cosmetic issues, minor UI glitches, etc.

A test plan is a document outlining the scope, approach, resources, and schedule for testing a software application.

• Identify test objectives and scope

• Define test strategies and methodologies

• List resources and tools required for testing

• Outline test schedule and milestones

• Specify test cases and scenarios

• Include risk assessment and mitigation plan

Various test cases can be applied to assess the quality and functionality of a bottle.

• Check for leaks by filling the bottle with water and shaking it

• Assess the durability by dropping the bottle from different heights

• Evaluate the seal by closing the bottle tightly and checking for any leaks

• Test the material of the bottle for any chemical reactions with different liquids

• Examine the cap for proper sealing and opening functionality

Regression, Sanity, and Smoke testing are different types of testing performed at different stages of the software development lifecycle.

• Regression testing is performed to ensure that new code changes have not adversely affected existing functionality.

• Sanity testing is a subset of regression testing and is performed to quickly determine if a new build is stable enough for more rigorous testing.

• Smoke testing is performed to check if the critical functionalities of the software...read more

There are multiple web element selectors used in QA testing, such as ID, class name, name, tag name, link text, partial link text, xpath, and css selector.

• ID selector - Selects an element based on its ID attribute

• Class name selector - Selects elements based on their class attribute

• Name selector - Selects elements based on their name attribute

• Tag name selector - Selects elements based on their tag name

• Link text selector - Selects elements based on their exact text

• Partial link...read more

QA's main work is to ensure quality of software by testing and identifying bugs and errors.

• QA's main work is to test software and identify bugs and errors

• They ensure that the software meets the requirements and specifications

• Bugs are coding mistakes that cause unexpected behavior

• Errors are mistakes made by the user that cause the software to fail

• QA engineers use various testing techniques to identify and report bugs and errors

Web locators include ID, name, class name, tag name, link text, and partial link text. Web driver supports implicit, explicit, and fluent waits.

• Web locators are used to identify elements on a web page

• ID and name locators are unique to an element

• Class name and tag name locators can identify multiple elements

• Link text and partial link text locators are used for links

• Implicit waits wait for a certain amount of time before throwing an exception

• Explicit waits wait for a certain co...read more

Quality is meeting or exceeding customer expectations through consistent and reliable performance.

• Quality is a measure of how well a product or service meets the needs and expectations of its users.

• It involves meeting or exceeding customer requirements through consistent and reliable performance.

• Quality can be achieved through effective planning, design, implementation, and monitoring of processes and systems.

• Examples of quality measures include customer satisfaction, defect ...read more

MQTT publish and subscribe work by clients connecting to a broker, where publishers send messages to topics and subscribers receive messages from those topics.

• Clients connect to a broker to publish or subscribe to topics

• Publishers send messages to specific topics on the broker

• Subscribers receive messages from topics they are subscribed to

• Broker manages the routing of messages between publishers and subscribers

Regression testing is retesting of software to ensure that recent changes have not adversely affected existing features. Regression defects are bugs that reappear after changes.

• Regression testing is performed to make sure that new code changes have not introduced any new bugs or caused existing functionalities to break.

• It involves re-executing test cases that cover the impacted areas of the software.

• Regression defects are bugs that were previously fixed but resurface after ne...read more

Test cases for a pen and water bottle include functionality, durability, and usability checks.

• Functionality test: Check if the pen writes smoothly and the water bottle opens and closes properly.

• Durability test: Drop the pen and water bottle from a certain height to check for damage.

• Usability test: Check if the pen is comfortable to hold and write with, and if the water bottle is easy to drink from.

• Leak test: Fill the water bottle with water and check for any leaks.

• Material te...read more

QA Engineer ensures software quality by planning, designing, and executing tests.

• Develop and execute test cases

• Identify and report defects

• Collaborate with developers to resolve issues

• Ensure compliance with quality standards

• Continuously improve testing processes

Answering programming questions related to string manipulation.

• To reverse a string, use a loop to iterate through the string and append each character to a new string in reverse order.

• To count the number of words in a string, split the string into an array using whitespace as the delimiter and return the length of the array.

• To swap two numbers without a temp variable, use arithmetic operations to perform the swap. For example, a = a + b; b = a - b; a = a - b;

Scenario based testing involves identifying the type of testing required based on a specific scenario.

• Identify the scenario and understand the requirements

• Determine the objectives of the testing

• Choose the appropriate testing types such as functional, regression, performance, etc.

• Design test cases based on the scenario

• Execute the tests and analyze the results

Encapsulation is the process of hiding internal implementation details and providing a public interface. Loading process refers to the steps involved in loading a program or data into memory.

• Encapsulation helps in achieving data abstraction and information hiding.

• It allows for better control over data and prevents unauthorized access.

• Loading process involves steps like parsing, linking, and loading the program or data into memory.

• Here's an example code for reversing a string:...read more

Encapsulation is the process of hiding internal details of an object and providing access only through defined methods.

• Encapsulation helps in achieving data abstraction and data hiding.

• It allows for better control over the data and prevents direct access to it.

• Loading process refers to the process of loading a program or data into memory for execution.

• Reverse string code example: function reverseString(str) { return str.split('').reverse().join(''); }

It is not safe to allow an adult to onboard a flight with 3 infants due to safety regulations and limitations.

• Safety regulations typically restrict the number of infants per adult on a flight for safety reasons.

• The adult may not be able to properly care for all 3 infants during the flight, leading to potential safety issues.

• The airline may have specific policies regarding the number of infants per adult allowed on a flight.

Use a loop to iterate through each word in the string and extract the first character of each word.

• Split the string into an array of words using a space as the delimiter

• Iterate through each word in the array and extract the first character of each word

• Store the first characters in a new array

Postman is a popular API testing tool used by QA Engineers to test APIs. Tokens can be saved in Postman using environment variables.

• Postman is an API testing tool used by QA Engineers.

• Tokens can be saved in Postman using environment variables.

• To save a token in Postman, you can create an environment variable and store the token value in it.

• You can then reference this environment variable in your requests to authenticate using the token.

Smoke testing is a preliminary testing technique to quickly identify major issues in a software build.

• Smoke testing is performed to ensure that the critical functionalities of the software are working as expected.

• It is a high-level testing that focuses on the most important features of the application.

• Smoke tests are usually executed after a new build or deployment to catch any showstopper bugs early.

• The main purpose is to verify if the software is stable enough for further t...read more

Different types of testing and their definitions, differences, and use cases.

• Unit testing: testing individual units or components of the software

• Integration testing: testing how different units or components work together

• System testing: testing the entire system as a whole

• Acceptance testing: testing if the system meets the requirements and is ready for release

• Regression testing: testing to ensure that changes or updates to the system have not caused any new issues

• Performance ...read more

Testing is the process of evaluating a system or application to identify defects or errors before it is released to users.

• Testing helps ensure that the software meets the requirements and functions correctly.

• It helps in identifying and fixing bugs or issues early in the development process.

• Testing improves the quality of the software and increases customer satisfaction.

• It helps in reducing the risk of software failures and costly rework.

• Types of testing include unit testing, ...read more

Quality is the degree of excellence of a product or service. 7 QC tools are used to identify and solve quality problems.

• Quality is meeting or exceeding customer expectations

• QC tools include Pareto chart, fishbone diagram, control chart, scatter diagram, histogram, flowchart, and check sheet

• These tools help identify and solve quality problems

• They are used in various industries such as manufacturing, healthcare, and software development

Priority refers to the order in which defects should be fixed, while severity refers to the impact of a defect on the system.

• Priority determines the order in which defects should be addressed, based on business needs and project timelines.

• Severity indicates the impact of a defect on the system's functionality or user experience.

• A defect with high severity may have a lower priority if it doesn't affect critical functionality.

• Examples: A spelling mistake in a non-critical area ...read more

Sanity testing is a narrow and focused testing to ensure basic functionality, while smoke testing is a broader and shallow testing to check major functionalities.

• Sanity testing is performed after receiving a software build to quickly check if it is stable enough for further testing.

• Smoke testing is performed to verify if the major functionalities of the software are working fine.

• Sanity testing is a subset of regression testing, focusing on specific areas of the software.

• Smoke...read more

Count the frequency of each alphabet in a string

• Create an array of size 26 to store the count of each alphabet

• Iterate through the string and increment the count of each alphabet in the array

• Convert characters to lowercase to handle case-insensitivity

• Ignore non-alphabetic characters

Validate input by checking for specific error messages instead of success message

• Check for error messages related to incorrect input (e.g. 'Invalid username/password')

• Verify the response code or status returned after login attempt

• Look for any specific patterns in the error messages that indicate incorrect input

To read data and assert with db value in API automation, use API response to extract data and compare with database query result.

• Extract data from API response using JSON parsing libraries like Gson or Jackson

• Execute database query to retrieve expected value

• Compare the extracted data with the database value using assertion libraries like TestNG or JUnit

Quality Assurance focuses on improving processes to prevent defects, while software testers focus on identifying defects through testing.

• Quality Assurance involves creating processes and standards to ensure quality in the software development lifecycle.

• Software testers focus on executing test cases to identify defects in the software.

• Quality Assurance is proactive in nature, aiming to prevent defects from occurring.

• Software testers are reactive, identifying and reporting defe...read more

Prioritize test cases based on criticality and impact, automate repetitive tests, and focus on high-risk areas.

• Prioritize test cases based on criticality and impact

• Automate repetitive tests using test automation tools

• Focus on high-risk areas to ensure maximum coverage in limited time

TestNG provides various built-in annotations to control the flow of test methods.

• Some of the common @Annotations in TestNG are @Test, @BeforeSuite, @AfterSuite, @BeforeTest, @AfterTest, @BeforeClass, @AfterClass, @BeforeMethod, @AfterMethod, @DataProvider, @Parameters, @Listeners, @Factory, @BeforeGroups, @AfterGroups, @BeforeSuite, @AfterSuite, @BeforeTest, @AfterTest.

• These annotations help in setting up preconditions, postconditions, grouping tests, parameterizing tests, an...read more

Selenium suite components include Selenium IDE, Selenium WebDriver, and Selenium Grid. Limitations include browser compatibility issues and difficulty in testing non-web applications.

• Selenium IDE for record and playback

• Selenium WebDriver for programmatic interaction

• Selenium Grid for distributed testing

• Browser compatibility issues

• Difficulty in testing non-web applications

I have encountered exceptions like ElementNotVisibleException, StaleElementReferenceException, TimeoutException, etc.

• ElementNotVisibleException occurs when an element is present in the DOM but not visible on the web page.

• StaleElementReferenceException occurs when an element is no longer attached to the DOM.

• TimeoutException occurs when a specific operation does not complete within a specified timeout.

• NoSuchElementException occurs when an element could not be found on the web p...read more

Sprint planning is a meeting where the team decides which work items to complete in the upcoming sprint.

• Sprint planning involves the team reviewing the product backlog and selecting user stories or tasks to work on during the sprint.

• The team estimates the effort required for each selected item and creates a sprint backlog.

• The duration of sprint planning is typically 4-8 hours for a 2-week sprint, but can vary based on team size and complexity of work.

• Sprint planning helps the...read more

The code for swapping numbers or alphabets in Python involves using a temporary variable to store one of the values.

• Create two variables to store the values to be swapped.

• Use a temporary variable to store one of the values.

• Assign the first value to the second variable and the temporary variable to the first variable.

XPath is more powerful and flexible but complex, while CSS selectors are simpler and faster.

• XPath can traverse both upwards and downwards in the DOM tree, while CSS selectors can only traverse downwards.

• XPath can select elements based on their attributes, text content, and position in the DOM, while CSS selectors are limited to selecting elements based on their attributes.

• XPath expressions are longer and more complex than CSS selectors, making them harder to write and maintai...read more

Yes, I am aware of Microsoft Excel and PowerPoint presentation.

• I have experience in using Microsoft Excel for data analysis and management.

• I have created and delivered presentations using Microsoft PowerPoint.

• I am familiar with the various features and functions of both applications.

I have experience in various types of testing including functional, regression, performance, and security testing.

• Functional testing - testing the functionality of the software against the requirements

• Regression testing - testing the software after changes have been made to ensure that existing functionality has not been affected

• Performance testing - testing the software's performance under different loads and conditions

• Security testing - testing the software's security featu...read more

Severity refers to the impact of a defect on the system, while priority refers to the order in which defects should be fixed.

• Severity is the measure of how impactful a defect is on the system's functionality.

• Priority is the order in which defects should be fixed, based on business needs or deadlines.

• Severity is usually categorized as low, medium, or high, while priority is often categorized as low, medium, or high as well.

• For example, a spelling mistake on a button may have l...read more

Yes, I am familiar with Google Cloud Platform (GCP) and BigQuery.

• I have experience working with GCP services such as Compute Engine, Cloud Storage, and BigQuery.

• I have used BigQuery for analyzing large datasets and running complex queries.

• I am familiar with setting up data pipelines and ETL processes using GCP services.

Test automation architecture involves designing frameworks, tools, and processes to automate testing. Test optimization techniques aim to improve efficiency and effectiveness of testing.

• Design a modular framework to promote reusability of test scripts

• Implement data-driven testing to cover various test scenarios

• Utilize continuous integration tools for automated test execution

• Leverage parallel testing to reduce overall test execution time

• Use risk-based testing to prioritize tes...read more

Code for overloading and sample code for OOPS concepts

• Overloading is when a function has the same name but different parameters

• Polymorphism is the ability of an object to take on many forms

• Inheritance is when a class inherits properties and methods from another class

• Encapsulation is the practice of keeping data and methods within a class

• Example: class Animal { void makeSound() { } } class Dog extends Animal { void makeSound() { bark(); } }

• Example: class Shape { void draw() { ...read more

Automation testing offers faster feedback, increased test coverage, and improved accuracy.

• Faster feedback on code changes

• Increased test coverage with the ability to run more tests in less time

• Improved accuracy and consistency of test results

• Reduced testing costs and time

• Ability to test in different environments and configurations

• Identification of defects earlier in the development cycle

• Improved team productivity and collaboration

• Ability to perform regression testing easily

• Exa...read more

To find elements not available in DOM in Selenium, use try-catch block to handle NoSuchElementException.

• Use try-catch block to handle NoSuchElementException when trying to find elements not available in DOM.

• Catch the exception and handle it appropriately in the code.

• Use WebDriverWait with ExpectedConditions to wait for the element to be present before interacting with it.

SDLC is Software Development Life Cycle, STLC is Software Testing Life Cycle. Function Testing tests individual functions of software, UI Testing tests user interface.

• SDLC is a process used by software development teams to design, develop, and test high-quality software.

• STLC is a process used by software testing teams to plan, design, execute, and report on testing activities.

• Function Testing involves testing individual functions or units of code to ensure they work correctly...read more

The main purpose of a Test Case is to verify that a specific functionality of the software is working correctly.

• Test Cases ensure that the software meets the specified requirements

• They help identify defects and ensure the software is reliable

• Test Cases provide documentation for future reference and regression testing

• They help in reproducing and fixing bugs

• Examples: Testing login functionality, verifying calculations in a financial application

Criteria of testing refers to the standards or requirements that must be met during the testing process. Testing strategies are the approaches or methods used to conduct testing effectively.

• Criteria of testing include functional requirements, performance benchmarks, usability standards, and security protocols.

• Testing strategies may involve manual testing, automated testing, regression testing, exploratory testing, and boundary testing.

• Test cases should be designed based on th...read more