Regression Testing: In-Depth Guide with Examples, Techniques and Actionable Tips


Are you searching for regression testing? Well, your search ends here.

In this article, we have covered everything from what and why to use cases, their types, real-life use of such testing, and best practices in detail!

So keep reading to get all your questions answers

What Is Regression Testing?

Due to updates or in the process of fixing bugs or adding new features, sometimes the software gets new errors or bugs.

 With regression testing, you can check all those codes that could be impacted due to new features or changes to ensure no new bugs are introduced in the tested code.

It ensures that the new changes or features have not spoiled or introduced bugs in the functional code.

This test is significant as it will add some features in your software that will provide convenience to your users, but due to those features, if bugs are introduced which are eroding the main functionality of your software, it will hamper the image and growth of your software.

What Is Automated Regression Testing?

As you understood in the early part, automated regression testing is just automating the process, i.e. many automation testing software like just automate this testing process for you. 

So you do not need to hire some manual tester or perform this testing on your own just get one software to complete your entire job; it will tell you which functionality has been hampered due to the introduction of new code.

Read also: What are the differences between Regression Testing and Retesting

Why Do We Need Such Testing?

If you search on Google the meaning of ‘Regression’, it means returning to a former or less developed state, sharing some, due to updating or adding a new feature, your application got in a bad state.

Like you might have also experienced after adding a new feature, some old features stop working correctly or software gets slow or some other issues, all these are due to bugs in the previous codes. So proper testing ensures that we can identify these bugs, or they can cause huge trouble.

Real-Life Example To Understand Regression Testing

Suppose you made one chatting application; you would have tested this application through a regression test and other testings. In that case, Suppose and solve lots of bugs before sending the final copy to the client. 

Now the client asked you to add some more features, so now you need to add new code for that features & then test the new code along with running this test for old codes to ensure that the old codes are not back. This is what regression testing is.


Types Of Regression Testing

#01 Unit Regression Testing

Focus on unit code while blocking all other interactions and dependencies outside the unit, narrowing down the testing making it less complex.

#02 Partial Regression Testing

Test bugs after adding new code to ensure that the software does not stop working. It ensures that code modifications do not affect the function and work as desired.

#03 Full or Complete Regression: 

Full or Complete testing is frequently performed when code changes for modification or software updates seep back into the roots. It is also done if there are numerous changes to the existing code. 

It provides a comprehensive perspective of the system and eliminates any unexpected issues. for a long period. 

Techniques or Methods of Regression Testing

#01 Retest All 

As the name implies, this regression testing technique entails recycling all test cases as well as evaluating all possible parts of the product or software regardless of whether a new modification is implemented in the software or not.

This method is time taking and tedious. This testing method s highly expensive because we have to test all elements of the product and all of the tests in the existing test.

When you modify only a small part of the program or product you should not perform retest-all.

#02 Selective Regression Testing

We use this technique to assess the effects of new code in the software on the already existing code. We leverage a portion of the current experiments to reduce the retesting work and selective testing costs.

A test case is re-executed with this technique whenever a new modification is introduced in any module or portion of the software or application, such as factors, capabilities, and so on. The condition between the experiment and the elements covered by the program is quite challenging to define in selective regression testing.

#03 Progressive Regression testing

We may use this technique when we introduce any new modifications in the software specification and write new test cases to run the appropriate tests. 

Advanced regression testing works extremely successfully when specific changes are included in the software’s specification and when new test cases are designed.

In this technique, we take a portion of the existing test cases and utilize them, saving the cost and work necessary to design all of the new test cases.

#04 Complete Regression Testing 

This has already been covered in the section on the different methods of regression testing.

When we introduce several changes into the software, thorough it comes into use more frequently, and also when the changes we make in the software affect the root or core of the product.

This is advantageous since it aids in the identification of previously undetected problems. After we complete the testing, we then send the final software or product to end consumers.

#05 Hybrid

The hybrid method combines Regression Test Selection and Test Case Prioritisation. Instead of selecting the whole test suite, choose only the re-executed test cases based on their priority.

#06 Test Case Prioritisation

Test cases with high priority are conducted first, followed by those with a medium or low focus. 

We can determine the importance of a test case by its criticality and impact on the product and the overall functionality of the product that is in use.

#07 Sprint Level Regression

Sprint Level Regression is performed mainly for new features or additions implemented in the most recent sprint. The test cases in the test suite are chosen based on the newly introduced functionality or enhancements.

#08 End-to-End Regression

End-to-End Regression covers all test cases that must be re-executed to test the entire product from beginning to end, encompassing all of the product’s fundamental functionalities.

Agile uses short sprints, and as the process progresses, it becomes increasingly important to automate the test suite. We must rerun the test cases in a short period of time. Automating test cases decreases execution time and bug slippage.

Regression Testing Best Practises

#01 Automated Regression tests 

Each system code build must undergo regression testing. However, automated regression tests can make the entire process much easier and more efficient, freeing QA testers to focus on the more sophisticated case-specific tests.

We can enable it by the code control system each time a build generates once they get automated. 

This ensures that we don’t change anything that reverses or corrects a previous feature. The following are the most typical categories that, in 99.99 percent of cases, demand automation:

We can quickly introduce the automated regression tests overnight or manually, freeing up precious resources. The primary benefit of automated regression tests is that manual testers may use the extra time to focus on exploratory tests of new features and assure a better UX.

#02 Run Full Regression only when required 

It is not necessary to run the entire regression suite on every build. In the case of a minor release, it is prudent to run or execute only the smoke tests and regression testing for any modules that have changed. 

To keep things easy, organize the test cases in regression testing according to the module of the AUT covered by each test. For example, suppose the release includes a change to the payment choices accepted by an online store. 

In that case, it is best to do regression testing for the payment procedure but skip regression testing for other features such as locating items and adding them to the basket.

#03 More Attention to Highly-Trafficked Paths

Such paths incorporate the app’s critical functionality and prominent features. It is essential to understand the primary customers and the typical highlights, traits, and collaborations they have primarily relied upon. 

The effective regression testing pack must incorporate tests that ensure this fundamental feature performs as expected.

Read also: 5 Things To Keep In Mind While Doing Regression Testing

Regression of GUI Application 

When the GUI structure changes, it is challenging to execute a GUI (Graphical User Interface) Regression test. The test cases written on the old GUI are either obsolete or we must change them.

When we reuse the regression test cases, the GUI test cases get changed to reflect the new GUI. However, if you have a significant number of GUI test cases, this work gets difficult.

Regression Testing in Agile 

In agile, testing must evolve with each sprint, and testers must ensure that new modifications do not interfere with the application’s existing functionality. This is what we call regression testing.

Regression testing verifies that the application’s previous functionality is still functional and that new changes have not introduced new bugs. Therefore, we must use regression testing for a minor localized change or a broader update to the software.
Teams must ensure that new code does not conflict with previous code and that non-changed code continues to function as planned.

There are numerous build cycles in agile, and we need to update the application regularly. As a result, regression testing is critical in agile. 

A testing team should build the regression suite from the beginning of product development for successful agile regression testing. Along with development sprints, they should continue to improve them.

Pros Of Regression Testing

  1. Regression testing is critical in an agile setting because the integration of prior and current releases must be verified with each sprint. It ensures that business processes continue to run smoothly.
  1. Regression testing aids in the identification of software bugs by detecting undefined integrations between components in an application. With regression tests, we can make the software more resistant to errors. This enables the testing teams to deliver the product quickly while maintaining quality assurance.
  1. Even with these frequent additions, regression testing guarantees that the application attempts to remain intact and integrated. Automated regression tests produce faster findings and repeat testing for similar releases. Allows you to track any type of problem in an application continuously.
  1. Regression testing aids in the reduction of avoidable costs associated with production events. Using automated software testing solutions reduces the overall cost of the project.
  1. Regression testing also aids in the implementation of a continuous integration setup in which, whenever a developer pushes code, a build is triggered, after which the regression test suite is automatically conducted to guarantee the smooth operation of the entire software.
  1. Automated regression test cases save a significant amount of time in execution because the same automated test scripts may be reused for testing and adjusted as needed.
  1. It encourages product quality enhancement and ensures that any changes we make do not influence the essential functionalities that have already been tested and confirmed.
  1. With regression, you can fix bugs before launcing the software in the market.
  1. Automated regression testing speeds up the testing process and reduces the testing lifespan. We can execute automation scripts nightly across multiple machines simultaneously. Once the automated regression test suite is complete and ready for execution, the test resources can shift their attention to other programme areas that require their expertise.

Cons Of Regression Testing

  1. Manual regression testing necessitates a significant amount of human labour and time, and it quickly becomes a complex procedure. If we don’t employ an automation testing tool, the testing process will be time-consuming for regression testing.
  1. We should do regression testing after every tiny modification in the code because even a tiny part of the code might cause problems in the product.
  1. It is necessary to perform regression testing periodically during the agile sprint.
  1. We must create large test scripts that take a long time to run for sophisticated functionalities. This may cause delay in the test execution process , and the testing team may fail to fulfil delivery deadlines.
  1. The testing team finds it challenging to identify the frequency of regression tests following each release and build bug patches.
  1. Due to a lack of understanding of the business requirements, it creates regression test suites incorrectly. If we don’t have sufficient regression test cases in place, the testing team may fail to test and report a significant feature fault.
  1. There will be problems organising regression testing if the testing team does not grasp the chosen software development process.
  1. If the testing team does not grasp the aim of regression testing, they will take incorrect actions during the regression test execution process.

Benefits Of Regression Testing

  1. Regression testing in agile enhances and maintains a product’s software quality. It increases the testing team’s confidence in providing high-quality, bug-free software to the customer.
  2. It ensures that the issues that have already been identified are fixed and that we are ready to release an efficient programme into production.
  3. Regression testing ensures that any changes to improve the product negatively impact the existing deployed code.
  4. Agile, automated regression testing is a critical part of software testing since it enhances test coverage in less time.
  5. Regression testing in agile aids in discovering problematic regions early on, allowing developers to replace that piece with suitable code rapidly. It also aids in achieving improved software stability.
  6. Because we automate the entire regression test scripts, they reduce overall execution time by saving significant time and effort.
  7. Because the tests produced during the cycle are reusable, the regression test suite from the previous process is readily available for the test execution phase of any following sprint cycle. Such software testing yields a good ROI (Return on Investment).
  8. Regression testing ensures that the final product delivered fulfils the customer’s expectations.
  9. It is agile entails running specific scenarios to confirm that the functionality functions appropriately.
  10. It informs the organisation about which flaw is creating troubles in the application following software modifications, preventing these occurrences into production.
  11. Regression testing in agile assures system stability while also improving the application.
  12. Because it repeats the same steps, enabling the team to provide higher-quality products to customers in fewer sprints.
  13. It is relatively cost-effective because automation saves time and manual labour on repetitive operations.

Problem And Solution To This Testing Process

  1. Costly: As it is a time-consuming, hectic job as you need to run lots of tests, so a manual tester will take a good amount of money from you and also will take a lot of your time, so the best solution for this is to use automation testing software like which eradicate all this issue and also a pocket-friendly solution.
  2. Complexity: Finding the errors or bugs in new features and. Checking if the old codes do not have any bugs makes the process very hectic and makes the testing a lot more complex as you need to test old and new test cases, which are very hectic jobs.
  3. A different approach: Not all codes and bugs are the same, so you need to conduct it with proper planning and the right approach; if not done correctly, bugs will not be eradicated, and doing this manually is a next-level challenge, even many of of the automated regression testing software takes time for some codes for eliminating this bugs so choosing a right automation testing software like makes the job more accessible and smooth.

Automated Regression Testing Tools

#01 Avo Assure

Avo Assure is a no-code, technology-agnostic test automation solution that allows you to test end-to-end business processes with a few mouse clicks. This simplifies and accelerates regression testing.


  • We can generate test cases automatically using a no-code technique.
  • With a single solution, you; if can test across the web, desktop, mobile, ERP apps, mainframes, related emulators, and more.
  • Make accessibility testing possible.
  • Intelligent Scheduling allows you to test cases in a single VM independently or parallel.
  • Integrate with Jira, Jenkins, ALM, QTest, Salesforce, Sauce Labs, TFS, and more applications.
  • You can define test plans and design test cases using the Mindmaps functionality.

#02 Eggplant

Eggplant’s AI-powered test automation accelerates it by prioritizing test cases and reducing test upkeep.


  • Eggplant can test the most critical aspects of each release thanks to AI-driven test execution.
  • Reusing testing models and scripts allows you to test numerous versions with a single set of assets.
  • Self-healing functional tests alleviate the load of test maintenance.
  • Recognise and concentrate on problematic areas of your application that jeopardise your release.
  • You can find bugs that you would have missed otherwise through automated exploratory testing.,; if
  • Reduce the time required to test essential application functionality following changes.

#03 Selenium 

Selenium is a lightweight open-source browser management tool that supports all popular operating systems and browsers. It supports PHP, Ruby, C++, Java, JS, Perl, Python, and C# languages. Selenium integrates with various frameworks like Maven, Ant, and others to streamline automated testing.


  • There is no need for server installation.
  • Command classification based on classes;
  • Selenium Remote Control; 
  • WebDriver API support

How To Get The Best Of Regression Testing?

The best way is to get the automation testing software like, which you can use multiple times on multiple software and their updates. Also, you will be able to keep proper track of automation software.

Make sure that you implement this testing framework at the very beginning of your project, which will save your cost, time, and energy in the future.

Keep a proper testing schedule, make sure that the project you test the project at every critical stage or after every update, ask your team to work on testing as it is a crucial step in the software development process.


Regression testing is a vital process, and you should make sure that you follow it from the very start of application development.

It is a great framework that saves a lot more time and checking, and updates or adding new features is an ongoing process and never going to end.

With software like, you can automate your testing. As we said, it is a very intensive task and time-consuming. Its requirement is endless, so hiring a team does not make sense and provides the best ROI. 

Instead, automation. If, and checking, are some testing software like, one of the best testing software. If, and checking, are some, it makes much more sense.