Sanity Testing Explained: Why It’s Important

Sanity testing is one of the first steps of the testing process, and its main goal is to check if the software still operates well under small or no changes. 

In software development, any code update, even a bug fix or a tiny feature update, can bring potential risks. No matter how small the modification is, the non-anticipated side effects can ripple across the application. Here sanity testing comes into play. 

Nonetheless, a lot of teams still disregard the importance of it and treat it as an optional measure rather than a must-have one. It is critical not to overlook this approach. A well-planned sanity test can be the difference between identifying a blocker issue early on and finding it only after conducting a regression testing—or even worse, in production mode. In this guide, we will go through the fundamental points of sanity testing, the importance of it and the time you should use the method effectively.

What is Sanity Testing?

Sanity testing is a targeted verification process that makes the app secure and assures that a recent change has not disrupted the core functionality of it. It’s a subset of regression tests, but it is much more focused and less formal.

Rather than checking the whole system, it only checks the affected module. It ensures that new fixes work and nothing else is broken before executing further testing.

A Real-World Perspective

Imagine yourself in a scenario where you are working on an e-commerce app. One day, a bug was reported that caused users not to be able to get the discount code at the checkout.

To find and address the issue, the developers resort to a quick fix. After the bug has been rectified, the testing process is to be commenced. 

Instead of testing every feature, test only the part where the discount code is applied during checkout to make sure that: 

Now, discount codes can be applied without any issues.

The other checkout steps also work (the payment and order confirmation). 

No new problems would arise in any of the other corresponding fields. 

If the sanity test is successful, it means that the build is good enough to move forward with regression testing. If the sanity test is unsuccessful, there is no use in wasting time running broader tests for the fix that needs immediate attention.

Why Is It Called “Sanity” Testing?

The name itself implies its purpose: to check the “sanity” of continuing the testing. If a build fails sanity testing, it’s a clear signal to the testers that further testing is pointless until the identified issues are resolved. 

Sanity testing is essentially a quick validation rather than exhaustive; it’s about fast and effective decision-making.

The ability to recognize its optimal use can protect the QA teams from unnecessary work and improve the general efficiency of the software testing cycle. 

Key Features and Scope of Sanity Testing

Sanity testing is not always an burdensome and excessive form of a control process, rather it’s a fast process of guaranteeing the quality of the development. 

Regression testing, on the other hand, is a comprehensive test that inspects the whole application, whereas, an in-depth test focusing only on the places affected by a bug fix or code modification is sanity testing.

Key Features of Sanity Testing

1. Narrow Focus, High Impact

• Sanity testing is comparatively shorter than regression testing since it focuses on specific parts of the applications instead of its entire scope.
• If a login issue was fixed, sanity testing would check login, session handling, and redirection but not the entire app flow.

2. Quick Execution

• It’s just an instantaneous, clear, direct, but not a detailed process that determines whether further testing is necessary or not.

3. Performed after minor code changes

• A sanity test is done unlike smoke testing, in which checks basic functionality of the new build is checked; it is generally performed after small fixes or enhancements to ensure their accuracy.
• Example: A patch to fix a cart calculation issue in an e-commerce app would require sanity testing on the checkout module but not on search or product pages.

4. Stops Unnecessary Regression Testing

• If sanity testing fails, there’s no point in running full regression testing.
• This saves time and prevents wasted effort on a build that isn’t ready for deeper testing.

5. It can be manual or automated

• Sanity tests are generally performed manually because of their sensitive and exploratory nature, but some of them can be made automated, which is true in CI/CD pipelines when there are too many small changes that need to be validated.

Objectives of Sanity Testing

1. Ensure That Bug Fixes Work as Expected

The main purpose of a sanity test is to confirm that a bug you previously reported actually was fixed without creating any new problems.

Example: For example, if a bug during the checkout process of a health application did not let users add coupon codes, the sanity test would be the one to ensure that:

• Coupons are added right this time.
• The payment procedure does not get affected. 
• The order acknowledgment still works as before.

2. Validate That New Changes Haven’t Introduced Critical Issues

It is normal for one problem to be solved while another one is accidentally introduced. Sanity Test, in this case, is a very reliable early warning system to avoid such issues.

Example: If a developer updates the travel booking site’s search algorithm. Then sanity testing would check whether: 

• Search results load correctly.
• Filters still work properly.
• Page navigation isn’t affected.

3. Avoid Wasting Time on a Broken Build

Sanity testing helps the testers to decide whether further testing is worth it or not. If the crucial function of the module is not correct, this will not be of any benefit moving forward with new cases related to the change. 

Example: In the case of a SaaS platform, a new login error occurs after the upgrade. The early detection of the issue by the sanity test facilitates the fixing before proceeding with the full regression test.

4. Improve Testing Efficiency

By focusing only on recently modified areas, sanity testing helps teams:

• Reduce test execution time.
• Prevent unnecessary retesting.
• Ensure faster feedback loops in agile development.

When Should You Perform Sanity Testing?

Sanity testing is a situational testing approach, as it isn’t a must for each build but is very important in certain circumstances. Times when to perform sanity tests are to guarantee that your QA procedure stays efficient.

Ideal Scenarios for Sanity Testing

1. After a Bug Fix

If a reported issue has been fixed, sanity testing ensures that the fix works without breaking related features.

Example: A login button did not work well on the mobile app. Sanity testing guarantees that:

• The button is now active. 
• The user can now successfully log in. 
• The home screen opens without an error message.

2. After a Minor Code Change or Patch

After small improvements or security patches have been added, sanity testing is done to ensure that the application’s stability is not affected. 

Example: A price calculation update in an e-commerce store. Sanity testing ensures:

• The checkout process has not messed up. 
• Discounts are applied properly.
• The final payment amount is on target.

3. Before Running Full Regression Testing

Instead of going into regression tests right away, sanity testing ensures that the app is still in a stable state.

For example, a new API integration for user authentication. Sanity testing would verify whether:

• Login through the new API is in the right condition.
• The present authentication methods still work with no problem. 
• The subscribers’ can access their accounts.

4. In Agile Development and CI/CD Pipelines

A frequent upgrade in Agile teams requires quick validation before full-scale testing.

Example: A weekly sprint update with UI changes. Checking sanity can be done with the standard procedures: 

• UI components are there, and we do not face any CSS or layout issues. 
• The core functionality is not changed and is still perfectly working.

Sanity testing is not a replacement for regression testing—it is a simple check to guarantee that the next nodal test is also justified. In the case of a sanity test being failed, it is impractical to carry out the deep tests until the problems are solved. 

Sanity Testing vs. Smoke Testing

Sanity testing is often mixed up with smoke testing, while they are actually different steps in the software test life cycle.

Key Differences Between Sanity Testing and Smoke Testing

When to Use Each Testing Approach?

Use Smoke Testing When:

• A new build is released, and you need to ensure basic functionality is intact. 
• You want to make sure the application can be tested properly before more complicated evaluation; the following should be installed. 
• Example: An updated version of a program that includes new features and bug fixes will be released. 

Use Sanity Testing When:

• A certain bug or a small alteration needs to be confirmed before performing the full tests.
• You want to prevent yourself from testing a broken build during regression testing. 
• For instance, a UI fix where the checkout button was not responsive, includes the intended outcome.

Real-World Example: Smoke vs. Sanity Testing

Imagine you are testing a ride-hailing app like Uber:

1. Smoke Testing Scenario

• A new build is released, adding ride-sharing features and bug fixes.
• Smoke testing checks:
   – Can users log in?
   – Can they search for a ride?
   – Does the app not crash on launch?

2. Sanity Testing Scenario

• A fix for incorrect fare calculations is implemented.

Sanity testing checks:

• Is the fare displayed correctly after applying a promo code?
• Are existing payment methods still working?
• Is there any unexpected UI behavior?

Step-by-Step Process of Performing Sanity Testing

Sanity testing is quick but structured in a thorough way. Because the objective is to verify the accuracy of the latest changes or fixes in a short period, all the necessary steps are mainly aimed at checking out the particular things without the resources of the unnecessary test cases. 

Step 1: Identify Impacted Modules or Features

• To find out what was changed, look at the bug fix report, patch notes, or change logs. 
• Find all the related components that may be affected due to dependencies. 
• For example, checkout may have been fixed in the bug if some areas to check are: Discount application, Payment processing, Order confirmation.

Step 2: Create Minimal Yet Effective Test Cases

Develop test cases that are specifically aimed at the verification of the fix and its immediate impact. 

• Be concise in your test cases—include only the most important steps.

Example: A sanity test can be formulated by fixing the problem of the login issue as follows:

• Type in proper login information and ensure it logs in successfully.
• Inspect error messages for the wrong passwords. 
• Make sure the user is redirected to the correct dashboard.

Step 3: Execute the Sanity Tests

Perform the tests manually once for one-time bug fixes or use automation for frequent sanity checks in a CI/CD pipeline.

If a lot of modules are affected, start with high-risk functionalities first, regardless of whether they are part of the same module or not. 

Example: A new API update was rolled out, and sanity testing was run to make sure that: 

• API endpoints respond as expected. 
• Authentication mechanisms operate in the way they are supposed to. 
• The system is down for a short time or not at all.

Step 4: Analyze Test Results and Identify Failures

• If the sanity test is passed, you should go ahead with deeper regression testing. 
• If it fails, you should not approve the build and report the issues to the team immediately. 
• Example: A sanity check on a banking app update finds that transfers work, but balance updates fail—testing stops until the issue is resolved.

Step 5: Decide Whether to Proceed with Further Testing

• If the sanity test fails, return the build to developers before spending time on full regression.
• If it passes, move ahead with more comprehensive testing. 
• For example, when updating a SaaS application, if dashboard analytics of sanity testing fail, there is no need to test the advanced reporting features.

Best Practices for Effective Sanity Testing

Sanity testing is conducted quickly, strategically, and consistently to make it the most effective. Here are expert-level best practices to guarantee the maximum efficiency in your testing workflow.

1. Focus on High-Impact Areas

• Do not test the entire application; rather, conduct the sanity tests where there is the highest possibility of the recent change. 
• Prioritize the crucial functions such as payments, authentication, date processing, and connecting APIs.
• Example: In an e-commerce site, sanity testing should just check the checkout issue. Homepage navigation tests should only be done after other tests have been completed.

2. Keep Test Cases Minimal Yet Effective

• Do not stack up the same test cases repeatedly. Sanity testing is to ensure quick validation and not to check every detail exhaustively. 
• Craft test scripts with a few lines of text that only verify the bug fix or feature enhancement.
• Example: Instead of testing all form fields in a login page, sanity testing only verifies that the password reset issue was fixed.

3. Automate When Possible (But Keep It Lightweight)

• Sanity tests should be automated in cases where the applications are updated frequently and each update needs a re-validation (especially in CI/CD pipelines). 
• Lightweight automation scripts should be employed instead of running whole regression suites. 

4. Integrate Sanity Testing in Agile and DevOps Workflows

• After every sprint update, the sanity tests in Agile development should run to check if new features didn’t break old ones. 
• Furthermore, in DevOps, sanity testing makes sure that CI/CD succeeds before the code is finally moved to production.

5. Document and Track Sanity Testing Results

• Keep a record of all the past sanity test outcomes in order to monitor repeating issues and patterns. 
• Use testing tools, e.g., JIRA, TestRail, and Zephyr, to log the results of test execution.
• Example: In cases where a database update frequently breaks login, documentation can show if these issues have been resolved or why they keep appearing.

6. Involve Developers in Sanity Testing Feedback

• As soon as the sanity testing session is over, share the report with the team to speed up the bug resolution. 
• The developers should have access to sanity test cases so they can cross-verify fixes even before sending the builds to the QA for further testing. 

Common Mistakes to Avoid in Sanity Testing

Sanity testing is expected to be a quick and efficient process, but teams often commit mistakes that are detrimental to its proper functioning. Here are some of the most common pitfalls and how to avoid them:

1. Over-Testing Unrelated Features

• Sanity testing through a specified part should not be regulated to a period of time. If this happens, however, it becomes redundancy checking.
• Fix: Focus only on the affected module and its immediate dependencies.

2. Skipping Sanity Testing Entirely

• The assumption that a minor fix does not need confirmation often becomes the cause of some bugs resurfacing again in production.
• Fix: Make sanity testing an obligatory process for every bug fix and patch.

3. Running Sanity Tests Too Late

• If you perform sanity testing after regression testing, then it defeats its purpose of catching early defects.
• Fix: Make sanity testing your very first step before you move on with any broader testing. 

4. Not Documenting Sanity Test Cases

• Without appropriate documentation, sanity tests become inconsistent across different testers.
• Fix: Use a simple checklist to list down sanity test scenarios and log those results in a test management tool.

5. Ignoring Dependencies Between Modules

• Changes conducted in one module may, however, also break the functions that are linked, which can sometimes be omitted from sanity testing.
• Fix: Identify the interconnected components and check their stability as well as the primary fix.

Advantages and Disadvantages of Sanity Testing

Sanity testing plays a crucial role in software quality assurance, but like any testing approach, it has its strengths and limitations.

Advantages of Sanity Testing

• The fact of Fast Execution – Since it only checks a small section of application and therefore saves time compared to a full regression test.
• Avoids Wasted Effort – if the build does not pass the sanity test, deeper testing is not needed to continue.
• Improves Bug Detection Efficiency – It identifies high-impacts defects early in the product development so that the rest of the build will be stable before further validation.
• Works Well in Agile and CI/CD Pipelines – Fits perfectly into continuous testing workflows, allowing teams to validate fixes quickly.

Disadvantages of Sanity Testing

• Low Test Coverage – It verifies only specific part of the application, and it can leave some defects unnoticed. 
• Lack of Replacement of Full Regression Testing – It is a method to ensure quick validation but it can not guarantee the overall stability of the system.
• Most of the Time it is a Manual Job – While automation is possible, many sanity tests are executed manually, which may slow down large-scale testing.

Frequently Asked Questions (FAQ) About Sanity Testing

1. Is sanity testing the same as regression testing?

• No, sanity testing is a subset of regression testing. Sanity testing only confirms the recent error correction or minor code change, whereas regression testing checks the whole application in order to find additional defects.

2. Can sanity testing be automated?

• Yes, but only for repeatable sanity tests that validate frequently modified features. For one-time fixes or UI-related issues, manual sanity testing is often more practical.

3. What happens if a sanity test fails?

• A failed sanity test instantly leads to the disapproval of the build, resulting in a report to the developers. Further testing is stopped; meanwhile, the defect should be fixed.

4. When should sanity testing be performed?

• After a bug fix, patch update, or minor code change, the testing of sanity should be carried out, which is required to see if the fix is successful. In addition, the related bugs have not been generated.

Strengthen Your Testing Process Now

Sanity testing is a crucial step in the software testing process, ensuring that recent fixes and minor updates do not introduce critical issues. By enabling quick validation, it helps teams catch high-impact defects early, maintain build stability, and avoid unnecessary regression testing.

For reliable and efficient testing, Testscenario offers professional testing services tailored to your needs. Whether you require comprehensive sanity testing or end-to-end quality assurance, We ensures your software remains stable and high-performing. Contact Us today and streamline your testing process for faster, more reliable software releases.