NUnit: How to Run Tests (Step-by-Step Guide for Beginners)

If you're working with .NET and need a powerful, open-source testing framework, NUnit is one of the best options available. Once you’ve written your test cases, the next step is running them. But how exactly do you run NUnit tests?

In this quick guide, you'll learn how to run NUnit tests using Visual Studio, the command line, and the NUnit Console Runner.

✅ Prerequisites

Before you run NUnit tests, make sure you have:

• .NET SDK installed
• NUnit and NUnit3TestAdapter installed via NuGet
• An IDE like Visual Studio or VS Code (optional)

🧪 Example NUnit Test

Here’s a simple NUnit test class:

using NUnit.Framework;

namespace MyApp.Tests
{
    public class MathTests
    {
        [Test]
        public void Add_TwoNumbers_ReturnsSum()
        {
            int result = 2 + 3;
            Assert.AreEqual(5, result);
        }
    }
}

🚀 How to Run NUnit Tests

🔹 Option 1: Run Tests in Visual Studio

1. Install the NUnit and NUnit3TestAdapter packages via NuGet.
2. Open Test Explorer: Test > Test Explorer or Ctrl+E, T.
3. Click Run All or select specific tests and click Run Selected Tests.

💡 Make sure the project has the [Test] attribute and builds correctly.

🔹 Option 2: Run NUnit Tests via Command Line

If you prefer the CLI, use the built-in dotnet test command:

dotnet test

This works with any .NET Core or .NET 5+ project that references NUnit.

To run a specific test class or method:

dotnet test --filter FullyQualifiedName~MyApp.Tests.MathTests

Or run a single method:

dotnet test --filter "Name=Add_TwoNumbers_ReturnsSum"

🔹 Option 3: Run with NUnit Console Runner (for .NET Framework)

For classic .NET Framework projects, you can use the NUnit Console Runner:

1. Install it from: NUnit Console GitHub
2. Run it via:

nunit3-console.exe path\to\YourTestProject.dll

You’ll see a full test report in the console or as an output file.

📂 Test Output and Results

• Test results are printed in the terminal or shown in the Test Explorer.
• You can generate .xml or .trx reports for CI/CD pipelines.

For example, with dotnet test:

dotnet test --logger "trx;LogFileName=test_results.trx"

📝 Summary

Running NUnit tests is simple once your project is properly configured. Whether you use Visual Studio or the command line, NUnit gives you flexibility and control.

🔁 Quick Recap: