NUnit vs SpecFlow comparison of testing frameworks
What are the differences between NUnit and SpecFlow?

	NUnit https://nunit.org/	SpecFlow https://specflow.org/
Programming language	.NET	.NET
Category	Unit Testing	Acceptance Testing
General info	NUnit is an open-source unit testing framework for Microsoft .NET. NUnit was Initially ported from JUnit. Tests can be run from a console runner, within Visual Studio through a Test Adapter or through 3rd party runners. Tests can be run in parallel and has Strong support for data driven tests. Unit supports multiple platforms including .NET Core, Xamarin Mobile, Compact Framework and Silverlight.	SpecFlow is a test automation solution for .NET SpecFlow is a test automation solution for .NET which follows the BDD paradigm, and is part of the Cucumber family. SpecFlow tests are written with Gherkin, using the official Gherkin parser which allows you to write test cases using natural languages and supports over 70 languages.
xUnit Set of frameworks originating from SUnit (Smalltalk's testing framework). They share similar structure and functionality.	Yes Nunit is one of many programs in the xUnit family	No
Client-side Allows testing code execution on the client, such as a web browser	Yes You can test front-end components with NUnit since it is a Unit testing framework the application is isolated into diverse modules which are tested independently	Yes Front-end behaviour is tested. With specflow specifications of the expected behaviours are made and specflow tests against this
Server-side Allows testing the bahovior of a server-side code	Yes You can test back-end components with NUnit, it is a Unit testing framework hence the application is isolated into diverse modules which are tested independently	Yes Back-end behaviour is tested. Specifications of the expected behaviours are made and specflow tests against them
Fixtures Allows defining a fixed, specific states of data (fixtures) that are test-local. This ensures specific environment for a single test	Yes NUnit contains the fixture methods SetUp to initialize your test environment and TearDown method to destroy a test environment	Yes BeforeTestRun and AfterTestRun are executed once for each thread which is a limitation of the current architecture.
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 Group fixtures are available in NUnit	N/A
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	Yes SpecFlow contains a generator component. The SpecFlow IDE integration tries to locate the generator component in your project structure, in order to use the generator version matching the SpecFlow runtime in your project
Licence Licence type governing the use and redistribution of the software	MIT License	BSD license
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 You can create mock objects using the third party library moq	Yes Specflow intergrates well with mock to give it excellent mocking capabilities
Grouping Allows organizing tests in groups	Yes You can group tests into suites with NUnit	Yes You can create test suites with specflow
Other Other useful information about the testing framework