Non-Functional Testing: A Complete Guide For Beginners

In this article, we are going to see Non-Functional Testing in detail. After you finished reading this blog post, you will learn the following.

Non-functional testing is a subset of Software Testing.

The types of testings are as follows

1. Functional testing
2. Non-functional testing
3. Maintenance testing

The list of testing types mentioned here is not the complete list. There are more than 100 types of testing.

In case you want to learn a detailed list of testing types, check out this 100+ Types of Testing.

What is Non-Functional Testing

Non-functional testing is a type of software testing which refers to various aspects of the software such as performance, load, stress, scalability, security, compatibility, etc., The main focus of non-functional testing is to improve the user experience on how fast the system responds to a request.

It covers all the areas that are not covered in functional testing.

It checks the attributes such as memory leaks, performance, or robustness of the system.
In simple words, how well the system performs is non-functionality testing.

Non-Functional Testing Types

The following are the most common types of Non-Functional Testing :

#1. Performance Testing

Performance testing determines how quickly an application performs in various situations. Learn more Performance Testing Tutorial

#2. Load Testing

Load testing is a test that looks at an app’s ability to function well when under peak conditions. Learn more Load Testing Tutorial

#3. Compatibility Testing

To test whether the application, website, or system under evaluation is suitable for a variety of environments such as web browsers, hardware platforms, databases, operating systems, networks, mobile devices, different versions and configurations. Learn more Compatibility Testing Tutorial

#4. Usability Testing

Usability Testing is a kind of testing that aims to determine how simple the software is to use. Learn more Usability Testing Tutorial

#5. Stress Testing

Stress testing subjects the system to severe conditions such as overloading it to see whether it can sustain the stress. Learn more Stress Testing Tutorial

#6. Volume Testing

Volume testing refers to the performance of a software application when it is exposed to a high amount of data. Learn more Volume Testing Tutorial

#7. Security Testing

Security testing is to ensure that the system protects data and continues to function as intended. Learn more Security Testing Tutorial

#8. Reliability Testing

Reliability testing is a kind of software testing procedure that validates whether the software application works correctly in a certain setting for a specific length of time. Learn more Reliability Testing Tutorial

#9. Endurance Testing

Endurance testing examines how a system behaves under a particular load for an extended period. We can assess the system’s behavior to ensure that the software is capable of withstanding high loads without decreasing latency. Learn more Endurance Testing Tutorial

#10. Documentation Testing

Document testing is the process of verifying that the documented artifacts produced before, during, and after the product’s testing are genuine. Learn more Documentation Testing Tutorial

#11. Localization Testing

Localization testing is to ensure that the application’s design is appealing to a specific culture, region, or local. Learn more Localization Testing Tutorial

#12. Internationalization Testing

Internationalisation testing is to ensure whether the applications are designed in such a way that it appeals to any culture, region or local.

#13. Baseline Testing

Benchmark testing is a proactive form of testing that is used to set performance goals and track progress over time. Learn more Baseline Testing Tutorial

#14. Portability testing

Portability testing is used to test how an application transfer from one software to another software. Learn more Portability Testing Tutorial

Some other common types of Non-Functional Testing are as follows

Recovery Testing
Resilience testing
Compliance Testing
Efficiency Testing
Failover Testing
Maintainability Testing
Scalability Testing

You can find detailed definitions of all the above-mentioned types of testing here.

Non-Functional Testing Parameters

Non-functional testing is done to test the non-functional parameters of an application. The parameters of non-functional testing are never tested before functional testing.

Non-functional parameters are as follows.

#1. Security

This parameter determines how a system is protected against planned and unpredictable attacks from both internal and external sources.

We perform Security Testing to validate this parameter.

#2. Reliability

The level to which any software system fulfills the required activities consistently and without error.

We perform Reliability Testing to validate this parameter.

#3. Survivability

The parameter ensures that the software system continues run smoothly and restores in the event of system failure.

We perform Recovery Testing to validate this parameter.

#4. Availability

The parameter determines how much the user can rely on the system during its operation.

We perform Stability Testing to validate this parameter.

#5. Usability

The convenience with which a user can learn, operate, input/output data through engagement with a system.

We perform Usability Testing to validate this parameter.

#6. Scalability

The term scalability refers to the software application’s ability in expanding its processing capacity in order to fulfill growing demand.

We perform Scalability Testing to validate this parameter.

#7. Interoperability

Interoperability validates the connections between a software system and other software systems.

We perform Interoperability Testing to validate this parameter.

#8. Efficiency

The degree to which a software application can handles capacity, quantity and response time.

#9. Flexibility

Flexibility refers to how quickly and simply the program can work in different hardware and software configurations.

#10. Portability

The flexibility of the software to shift from its existing hardware or software configuration.

#11. Reusability

Reusability referes to a portion of software application that can be adapted for use in another software application.

Advantages of Non-functional testing

The following are some of the benefits of performing a non-functional test:

It improves the performance of the application. Ensures the application runs smoothly and efficiently for large numbers of users simultaneously without any loading issues.
It improves the security of the application. Protects the applicatoin from hacking.
It includes testing that isn’t possible or covered in functional testing.

Disadvantages of Non-functional testing

The following are some of the disadvantages of non-functional testing:

Non-functional tests need to be executed again whenever the software is updated.
Users must pay to re-examine the software as a result of software upgrades, making it prohibitively expensive.

Functional Testing vs Non-Functional Testing

Earlier we have discussed the difference between functional testing and non-functional testing. Check this post for a detailed explanation.

Non-Functional Testing Tools

Non-functional testing can be done using different tools. There are several tools available in the market for Performance testing, Load testing, & Stress Testing.

Check this post for a detailed list of Performance Testing Tools and Security Testing Tools

In conclusion

Non-functional testing is an important testing type of software testing. It involves testing only non-functional requirements such as performance, security, usability, reliability, and other non-functional parameters.

Software testing is not considered complete with just finishing functional testing. Both functional and non-functional testing is important in the success of an application and builds up a good relationship with the customer.

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