What’s the Difference Between Functional and Non-Functional Testing?

Logix Guru

Developing a new application is a lengthy process that involves a high level of expertise. Developers spend hours upon hours crafting the code that leads to a tangible interface, page interactions, and a functional platform as a whole. However, like in nearly all business sectors, it’s extremely difficult to check your own work and ensure things function properly with an unbiased view. That’s where Logix Guru comes in with software, application, and database testing abilities that can ensure your hours of work into your interface results in a perfectly functional product. Two main types of tests go into this step of the testing process - functional and non-functional testing - which each iron out issues in the interface. But what’s the difference between these two types of testing? Logix Guru is here to break it down for you.

Who Needs Functional and Non-Functional Testing?

Knowing If Your Business Need Software, Application, or Database Testing

Database design

One of the biggest questions we get is asking whether or not a company needs functional or non-functional testing for their applications. While the obvious answer is yes if you want your time and labor to be properly spent in developing the best application possible, some businesses may not put a lot of value into the initial development stages of a certain application.

As time goes on, however, and the new software or application plans to launch, it’s extremely important to complete the necessary testing to ensure your applications do what they are supposed to do. This isn’t just for bug-fixing purposes, though. The software, applications, and databases being created often serve an extremely important purpose in the grand scheme of your business. These applications are developed to manage finances, invoices, carry out the day-to-day of your business and so much more, which is why it’s vital to use functional and non-functional testing for your application development.

Pittsburgh Software Testing

Functional Testing

Baseline Functions Put to the Test During Your Software or Database Testing

Functional testing is exactly what it sounds like: the base-level testing that checks to ensure that all functions of your software, application, or database work the way they are supposed to work. When coding, developers have a set of functional requirements and specifications they have to adhere to. These requirements break down everything from page interaction to data flow access, creating a roadmap that outlines what occurs when something is clicked or opened, where it leads, and where that page can then lead.

Because functional testing is so integral to the way testing is done, it is typically performed manually by a human who is given the same requirements and specifications. This tester validates the actions of the interface to ensure that the process follows all requirements necessary and does so correctly. This ensures the application is in the purest sense usable, weeding out failed test functions and conditions that cause errors. Some of the tests that are part of this process include:

  • Unit testing
  • Smoke testing
  • User acceptance testing
  • Integration testing
  • Regression testing
  • Interoperability tests

By the end, the developer knows precisely which aspects of the code need adjustments and where errors lie. Because fixing one portion of the software can cause harm to another, functional testing is often performed several times before the function is perfect.

Non-Functional Testing

Software, Application, and Database Testing Methods for Performance

After functional testing occurs, application testing typically moves into non-functional testing: the testing designed the ensure performance and usability of software, applications, and databases. As opposed to functional test, non-functional testing is less concerned about the functions doing what they are designed to do and more focused on user-based interactions. For this reason, non-functional testing looks at less tangible aspects of the interface like performance, usability, and reliability.

While this seems a little bit meta to think of the difference between functional and non-functional testing, the whole point of non-functional testing is to validate the performance and user-facing  actions of the software. This is typically done with automated tools because it is heavily embedded in timing, the existence of certain security methods, and how usable the software itself is. Much like functional testing, it is still engrained in specifications handed to the developer,  but these fixes typically exist on top of the functionally-tested pieces.

The customer-facing nature of non-functional testing means that non-functional testing is important in ensuring good UX in a software or application design. For this reason, many of the following tests will often be performed:

  • Performance testing
  • Volume
  • Security
  • Usability
  • Load
  • Stress
  • And compliance testing

Using these tests, it’s easy for database testing professionals to ensure proper performance, security, and optimum efficiency in the functions carried out by their software.


If you’re developing new software, taking the time for function and non-functional testing is the best way to ensure your application functions but also is a good investment for your company. Get in touch with Logix Guru today for all your QA, application, software, and database testing needs and see the difference expert testing can make in your development process.

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