TestNG vs JUnit comparison of testing frameworks
What are the differences between TestNG and JUnit?

	TestNG https://testng.org/doc/documentation-main.html	JUnit https://junit.org/junit5/
Programming language	Java	Java
Category	Unit Testing, Intergration Testing, End-to-End Testing	Unit Testing, Regression Testing
General info	TestNG is a testing framework for the Java programming language inspired by JUnit and NUnit TestNG is similar to JUnit and NUnit but with newer functionalities such as: annotations, test that your code is multithread safe, flexible test configuration, support for data-driven testing (with @DataProvider), support for parameters, powerful execution model (no more TestSuite) and more... It's also designed to cover all categories of tests unit, functional, end-to-end, intergration... etc	JUnit is an open source Unit testing framework for java JUnit is useful for developers to write and run repeatable tests. JUnit has been crucial in the development of test driven development and is partof the xUnit family of unit testing frameworks
xUnit Set of frameworks originating from SUnit (Smalltalk's testing framework). They share similar structure and functionality.	No	Yes It is an instance of the xUnit architecture for unit testing frameworks.
Client-side Allows testing code execution on the client, such as a web browser	Yes The scope of testing with testNg is wide and you can test various front-end functionalities and behaviours with it	Yes You can test front-end components such as individual classes and functions that create the front-end
Server-side Allows testing the bahovior of a server-side code	Yes You can test server-side functionalities and behaviours with TestNg	Yes You can test classes and functions that compose the back-end such as database connections and so on
Fixtures Allows defining a fixed, specific states of data (fixtures) that are test-local. This ensures specific environment for a single test	Yes Fixtures are inbuilt into testNG, these are the annotations which are: @BeforeSuite, @AfterSuite, @BeforeTest, @AfterTest, @BeforeGroups, @AfterGroups, @BeforeClass, @AfterClass, @BeforeMethod, @AfterMethod	Yes JUnit contains a setUp() method, which runs before every test invocation and a tearDown() method, which runs after every test method.
Group fixtures Allows defining a fixed, specific states of data for a group of tests (group-fixtures). This ensures specific environment for a given group of tests.	Yes You can use various fixtures to setup environments for group tests	Yes You can use setUp() and tearDown() inbuilt functions as group fixtures.
Generators Supports data generators for tests. Data generators generate input data for test. The test is then run for each input data produced in this way.	N/A	You can use JUnit-quickcheck to generate test data
Licence Licence type governing the use and redistribution of the software	Apache License 2.0
Mocks Mocks are objects that simulate the behavior of real objects. Using mocks allows testing some part of the code in isolation (with other parts mocked when needed)	Yes By Use of an external library like mockit which intergrates well with testNG	JUnit does not support mocking internally but you can use a mock framework like Mockito to generate mock objects.
Grouping Allows organizing tests in groups	Yes Multiple test cases can be grouped more easily by converting them into testng.xml file, in which you can make priorities which test case should be executed first	Yes In JUnit you can create a test suite that bundles a few unit test cases and runs them together. You use both @RunWith and @Suite annotation are used to run the suite test.
Other Other useful information about the testing framework