What is Non-Functional Testing? A Guide for Beginners

Have you ever wondered why non-functional testing is a primary area of focus for modern software development initiatives? In the past, quality assurance practices focused more on functional testing and rarely ventured into different non-functional testing types.
However, as the digital economy expanded, software transitioned from an enabler to a core pillar of success in businesses across different sectors. The dependence on software to drive revenue and value generation brought about the necessity to increase the scope of coverage for testing initiatives.
Therefore, non-functional test activities came into the limelight. However, a large section of technology and QA professionals have limited awareness of the need for non-functional testing.
They must understand what non functional testing is and why they must encourage it as a practice for enterprise application development projects.
What is Non-Functional Testing?

Non-functional testing validates the non-functional requirements of an application. Non-functional requirements (NFRs) are quality attributes of a software. For example, scalability, security, maintainability, reliability, interoperability, usability, capability, availability, etc., are all NFRs.
So, non-functional testing is concerned with testing how the system should do as opposed to functional testing, which validates what the system should do. For successful non-functional testing, it is important to:
- Consider all the applicable non-functional requirements or quality parameters
- Quantify each non-functional requirement
How is this advantageous? In essence, non-functional testing helps businesses to:
- Ensure that their software is secure
- Ensure that the functionality is suited to the users’ needs
- Enhance the overall quality and efficiency of the software
- Ensure that the software can accommodate load, availability, and other performance requirements
SUGGESTED READ - Functional vs. Non-functional Testing
What Are the Different Non-Functional Testing Types?

Over time, several new forms of non-functional testing types emerged from different industries depending on the specific use cases in that sector. For instance, testing approaches range from those developed for cloud applications to 3rd-party SaaS application testing procedures (for example, Salesforce testing or Workday testing). Altogether, several new areas to focus emerge when it comes to non-functional testing.
However, let us not elaborate on all known non functional testing types and explore the most popular ones in this blog.
Here are our picks for the top 10 non-functional testing types popular today:
Load Testing
Load testing deals with validating an application’s ability to perform optimally when there is excessive usage or under peak working conditions.
Performance Testing
With increasing competition and the fast-paced needs of today’s digital-savvy customers, performance occupies a core part of the overall customer experience for any software. Therefore, performance testing is of paramount importance. It validates the speed and responsiveness of an application when subjected to different workloads.
Usability Testing
Usability testing verifies the simplicity of use for an application. In other words, it evaluates how easily users can find their way through the application in any interaction.
Compatibility Testing
Compatibility testing checks for the workability of an application across a range of enabling environments. Typical areas of compatibility checked are different web browsers, smartphone variants, hardware platforms, networks, databases, and much more.
Volume Testing
Volume testing relates to stress testing. It checks an application's normal functioning when exposed to a large volume of data that needs processing or computation.
Security Testing
Security testing deals with one of the most important aspects of modern digital applications – secure customer data management. As more digital services consume confidential customer data, businesses must ensure that the acquired data is safeguarded against all threats. Failure to do so may attract heavy fines and penalties. Security testing checks for any vulnerabilities in the application, which, if left unattended, can lead to serious attacks from cybercriminals.
Localization Testing
Businesses seek to offer personalized services to customers via their digital applications and services. However, a significant portion of the personalization initiative depends on how well the application addresses the local needs. These needs could be demographic preferences, language options, budget preferences, and much more. Localization testing deals with verifying an application to see whether it fits well with cultural, societal, and market trends of a specific location or region.
Portability Testing
To expand digital capabilities, enterprises must often integrate different digital services with one another. While functional testing handles verification and validation at a code level for the integration, there is a need to check the non-functional aspects. To that end, portability testing checks for how well an application can interoperate or engage in transfer interactions between different applications.
Documentation Testing
Documentation testing verifies the authenticity and genuineness of all artifacts documented before and after the testing of the software. The user manual is one of the critical documents verified in this non-functional test. More profoundly, documentation testing verifies whether the data captured and documented in the manual is exactly what the system does in real-time.
Recovery Testing
Recovery testing checks for the ability of the application to recover its optimal performance after unexpected events like hardware failure, technical errors, crashes, etc. As more critical customer services are increasingly being handled by digital services today, recovery testing finds a very prominent place amongst non-functional testing types.
How Can Enterprises Drive the Best ROI From Their Non-Functional Testing Initiatives?
Non-functional testing is as vital for organizations as other core testing practices that attract attention like regression testing, end-to-end automation testing, etc. With increased patronage for cloud services, organizations must deliver seamless experiences to customers irrespective of their location, internet bandwidth, and access device. To ensure the fulfillment of customer expectations, non-functional testing takes center stage in an organization’s quality ambitions.
However, to achieve the most ROI from non-functional testing initiatives, enterprises must bring in automation across the non-functional test landscape. This is where ACCELQ can be a transformational partner.
Get in touch with us for a free trial of our test automation platform. See how your enterprise applications can enjoy unbiased and automated non-functional testing initiatives courtesy of ACCELQ’s comprehensive suite of test automation solutions.
Nidhi Achhaa
Content Specialist at ACCELQ
Nidhi specializes in technology-based content and strives to create a unique, customized, and compelling piece with a flavor of SEO. A writer with a love for words and a storyteller at heart.