What Is The Difference Between System Testing And End to End Testing?


Both system and end to end testing hold very important positions in the Quality Assurance process of a software. Testing is that stage in the software development life cycle at which the development that has occurred is verified.

The outcomes of testing are either that the software is working as expected or it will detect some defects and the software will be returned to the development team for correction. 

The testing process involves four levels:

1. Unit Testing: 

This testing is done by developers to check a recently coded unit or a module.

2. Integration Testing:

This testing is done before integrating a unit tested the module with the rest of the program.

3. System Testing:

When all the components are integrated and the complete model of the software is created then system testing is done.

4. End to End Testing:

This test is done to execute the software from beginning to end like a user

This software will keep on rotating in this cycle until it passes the testing stage with detection of any defect.

One difference between System testing and End to end testing is the level at which each of these testings is done. 

system testing and end to end testing
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Before knowing ‘how both of these testing methodologies are different from each other?’ we will discuss them in detail.

System Testing in Software Testing

At system testing stage, the software is completely developed to work as per specifications from the developer’s side and the final product will almost stay the same, though the software may have some bugs or defects.

Till this testing, all the components are integrated to work as one and the task of system testing is to check ‘if all the requirements and features are working in the desired way?’. 

System testing is a kind of Black Box testing, which means it has nothing to do with the code written or ‘how the workflow of the software is designed?’. It only cares about ‘if the system is good enough to satisfy the needs decided at the beginning of the software development life cycle?’.

The outcome of the testing is decided based on the ease of interaction with the software and comparison between the expected result and the actual result for a given input or instruction.

Functional testing is a major part of the system testing but along with that it also focuses on the performance testing of software.

Performance testing checks the working efficiency of the software when executed under various real-life loads and working conditions like different networks.

Security testing and Usability testing are also considered under system testing to ensure ‘if the application is safe and easy to use?’. Security of the data a user provide and store on the software is one of their major concern.

Even accessibility testing is also important to check the compliance of the software with the various protocols so that all the users can access the software easily.

system testing and end to end testing
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The testing will check for everything the stakeholders want to be present on the final product and let the team know about the scope of possible improvement.

System testing can be completed using automated tools available in the market like Selenium, Appium.

E2E Testing in Software Testing

End to end testing is carried out after the system testing to check the working of the software from its beginning to the end. It tests for the efficiency of the software to accomplish the task that requires it to interact with interfaces available outside the system’s environment.

E2E testing is the overall testing of the software and carried out with keeping user experience on focus. The software is executed the way a user will be handling it to perform some task.

It ensures that ‘if all the components within and outside the system are working properly with each other to accomplish a task and there is no hurdle in a feature’s path to behave the way it should be?’.

The software is tested by making it to interact with databases, network, hardware, and other applications. It helps in identifying the weak links in the communication between these components.

When software needs to work in collaboration with other application than it becomes necessary to implement those actions again and again before the user will perform them.

End to end testing is not a quick process it requires time and efforts. The testing should be done thoroughly to assure quality user experience. The productivity of the test depends upon the knowledge a tester have about the system and its subsystems.

Even it cannot be left on automatic tools to perform the test as writing tests for dependent applications are very complex.

system testing and end to end testing
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System testing ensures that the software is working as per expectations in itself but E2E testing ensures that the software is compatible to work with the subsystems, it is dependent on for some of its functioning.

Difference Between System Testing And End to End Testing

System TestingEnd to End Testing
This testing validates ‘if the software meets all the requirements and the specifications or not?’ and the system works as expected in itself.This testing not only validates the workflow of the software is in itself but also it’s subsystems.
It tests for the proper working of the functionalities and the features of the software.It tests the working of the software from its beginning to the end it includes every component of the software.
At this level only the functional and non-functional testing is done.At this level, the communication within the system and with all the interfaces like with the backend and the subsystems is tested.
This testing is done after the integration testing.This testing is done after system testing is over.
System testing can be done automatically or manually as per requirement.Manual E2E testing is preferred over automated testing as it is very complex to write test cases to run automatically for systems that work in integration with multiple systems.
system testing and end to end testing
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System Testing and E2E testing helps in bringing bugs to the knowledge of the developer’s team when the basic development of the software is almost done.

This is how the Quality Assurance team can get the product ready for deployment.