Difference between Smoke Testing and Regression Testing?

What is Smoke testing?

The testing method determines the stability of a deployed software build. It provides a sort of confirmation to the QA team to carry on with different levels of testing. A minimal set of tests are run on each build to test software functionalities. This testing method ensures that there are no show-stoppers in the build during the testing process. It is also known as “Build verification testing.”

What is Regression testing?

It is a testing method that ensures the new changes introduced in the code do not alter or modify the existing functionalities of a software application. Already executed test cases are partially or fully selected and then re-executed to ensure that the existing functionalities are working as expected. The objective is to ensure that the existing functionalities are working fine despite making changes or adding new features to the code.

Following are the differences between smoke testing and regression testing:

Smoke testing	Regression testing
In simple terms, smoke testing meaning - it verifies the crucial features and build the stability	Regression testing ensures that the change hasn’t affected any existing functionality
Regression testing includes the test cases of a smoke test and covers only the core functionalities	The test cases are obtained from Software Requirement Specification (SRS) or functional specification
Developers and testers are responsible for performing smoke tests	Testers are responsible for performing regression tests
The cost involved in conducting the testing is relatively low	The cost involved in conducting the testing is quite high
The testing process is conducted quickly to confirm whether to reject or accept a build	Regression tests are not accountable for rejecting or accepting a build
It is a surface-level testing where the system’s stability is verified	It is a deep-level testing where the system’s rationality is verified
This testing method is always followed by a regression test	This testing method is performed throughout the testing phase
This testing method is scripted or documented	This testing method is neither scripted nor documented
There is not much effort, resources, and time required to conduct the testing	There is a lot of effort, time, and resources required to conduct the testing.
It is an acceptance type of testing where the build is validated so that further testing is prevented  If it doesn’t pass	It is not an acceptance type of testing, and the functionalities are tested.