Different Types of Nonfunctional Testing

Nonfunctional Testing

Nonfunctional testing is used to evaluate the software’s nonfunctional characteristics, such as its dependability, performance under load, and accountability. Nonfunctional testing’s main objective is to assess the software system’s reading speed using nonfunctional criteria. It is never necessary to evaluate the broken testing parameters before the functional testing.

Due to its critical role in customer satisfaction, nonfunctional testing is just as vital as functional testing. Nonfunctional testing, for instance, might check how many people can use any given piece of software at once.

What is nonfunctional testing?    

Nonfunctional testing is a sort of testing used to assess a software program’s functionality, reliability, performance, and other broken aspects. Its goal is to evaluate a system’s readiness using nonfunctional standards that functional testing never considers. During nonfunctional testing, a software program or system is tested for its nonfunctional requirements—the way the system functions rather than particular behaviors. This contrasts with functional testing, which verifies compliance with operational requirements that specify how a system and its parts should work. Because many nonfunctional requirements have overlaps in their scope, the titles of several broken tests are frequently used interchangeably.

Confirming the software’s dependability and functionality requires nonfunctional testing. This software testing technique is based on the Software Requirements Specification (SRS), which enables quality assurance teams to determine whether the system meets user requirements. Nonfunctional testing aims to improve the product’s usability, efficacy, maintainability, and portability. It helps to reduce the production risk brought on by the product’s nonfunctional parts.

Examples of nonfunctional testing

While nonfunctional testing verifies that the application functions well enough to meet business requirements, functional testing tests its functionality and confirms that it performs as expected. Let’s look at a brief example to help you grasp its significance:

Although an application is created and thoroughly tested for functionality, it does not also undergo nonfunctional testing. When the program becomes life, however, it may cause severe or critical problems, such as when the load on the application increases and it becomes prolonged and takes a long time to launch. When the shipment is substantially increased, response time may worsen, or the application may crash. This demonstrates how crucial it is to test the nonfunctional components of an application.

Types of nonfunctional testing

Nonfunctional testing might be of many distinct forms. The most typical examples are: 

Performance Evaluations

Performance testing evaluates the functionality of software components. These tests reveal weaknesses in the performance of software architecture and design. Usually, this is carried out by:

  • Response time measurement
  • The detection of bottlenecks
  • Finding weak areas
  • Software quality is ensured via performance tests. They confirm its quickness, scalability, stability, and dependability.

Tests for Load

The software’s performance under average and busy situations is examined during load testing. This is done to find out how much work the software can manage before performance suffers. You can perform load tests by putting a server through a lot of traffic, running several applications simultaneously, or downloading many files. To verify that software is quick and scalable, load testing is utilized.

Stress Tests 

Stress testing examines how the program responds to unusual situations. This establishes the threshold at which the software will malfunction. Understanding what transpires when the system is under stress is crucial. Is the appropriate error message visible? Is the system broken? How will it bounce back? Stress tests are used to examine what transpires if a system fails. By doing this, the software is guaranteed to be recoverable, trustworthy, and stable.

Tests of Volume

When a significant amount of data is added to the database, volume testing determines what effect this has on the system’s performance. This is done to determine what issues might arise with growing data quantities. It is often referred to as a flood test. Volume tests can be used to check for data loss, error or warning messages, and storage problems. Volume tests ensure that systems react as anticipated to specific data volumes. For the sake of performance and stability, this is crucial.

Safety checks

Software is tested for security issues that could compromise data. Security testing aims to demonstrate that an attack won’t take place. Standard security examinations comprise:

  • Vulnerability assessments
  • Security checkups
  • Testing for penetration
  • Risk evaluation
  • Audits of security
  • Posture evaluation
  • Reputable hacking

It’s crucial to run these tests to create a secure and reliable system.

Installation and Upgrade Tests

Software compatibility testing ensures that upgrades and installations go smoothly on all machines. Upgrade testing is thus carried out for current users. Additionally, new users’ installations are tested. Both functional test types’ success is crucial for user satisfaction.

Restoration Tests

Recovery testing determines how quickly software can recover from a crash or failure. To accomplish this, the system is made to fail. This kind of testing is carried out to determine what occurs:

  • In case you unplug the hardware from the software.
  • If a data transfer is taking place when you open from the network.
  • When you unintentionally restart the system.
  • To enhance software performance, recovery testing is crucial

Testing the installation

Installation testing is done to ensure the user has no problems installing the software. This is so because a user interacts with a program for the first time during installation.

Testing for uninstallation                                

During uninstallation testing, the program is examined to ensure that all its components have been removed and that no mistakes have been left behind.

Testing for recovery

Recovery testing verifies that data is recovered in the event of any loss, including a power outage, an application breakdown, etc.

Testing of the documentation

Documentation testing is done to ensure that all papers necessary for the technical use and upkeep of the program are present and consistent.

Testing the user interface          

Application designs are subjected to user interface testing. It ensures that each component of the interface functions as it should.

How to do nonfunctional tests?

To do the nonfunctional tests, some parameters are fundamental. Without these parameters, you cannot do nonfunctional testing. These parameters are:

In general, performing manual nonfunctional testing is challenging. For instance, manually logging in with numerous users is tricky and requires significant resources. Additionally, it will take time, and the anticipated outcomes cannot be obtained. An efficient and time-saving choice is to use an automated testing program. As a result, several computerized tools exist for the same access on the market. The list of automation tools used by testers around the world is provided below:

Apache JMeter

A Java-based performance testing tool called JMeter. It is free, open-source software that runs on all platforms. Additionally, it supports Selenium integration and functions as a unit testing tool.

LoadRunner –

Similar to JMeter, LoadRunner is a performance testing tool that may also be used for integration and unit testing. It is the industry leader in performance testing. LoadRunner also supports scripts from JMeter and Selenium by announcing an interface library. Although it costs money, a limited number of people can utilize the trial version.


This is a Java-based performance testing tool. One of their several pricing tiers is free, but it only accepts a certain number of people. Additionally, it supports current Java-based Selenium scripts.

Another performance testing tool with a range of payment options is WebLOAD Professional, which also offers a free subscription with a constrained number of users. Additionally, Perfecto Mobile and Selenium are supported. A performance testing tool called LoadTracer was created in C by Trace Technologies Pvt. Ltd. It is currently available without charge.

Difference between functional and non-functional testing  

A sort of testing called functional testing ensures that every feature of a software application works under the requirements. Black box testing makes up most of this testing, which is unconcerned with the application’s source code.

Every aspect of the system’s functionality is tested by giving the correct input, confirming the output, and contrasting the actual outcomes with the predicted ones. The user interface, APIs, databases, security, client/server programs, and application functionality are all tested during this process. Testing can be carried out manually or automatically.

Definition of Nonfunctional Testing: What Is It?                   

Definition of Nonfunctional Testing: What Is It?                   
Image source: Perfecto

Nonfunctional testing is a sort of testing used to evaluate a software application’s nonfunctional characteristics, such as its performance, usability, dependability, etc. It is specifically intended to verify a system’s readiness according to nonfunctional criteria, which functional testing never addresses. A practical nonfunctional test would determine how many users can sign in to a program. Client satisfaction is impacted by nonfunctional testing, which is just as important as functional testing.

The essential difference between functional and non functionality testing   

  • While nonfunctional factors like performance, usability, reliability, etc., are verified by nonfunctional testing, each function or feature of the software is verified by functional testing.
  • While nonfunctional testing is challenging to carry out manually, functional testing can be done.
  • While nonfunctional testing is based on client expectations, functional testing is based on customer requirements.
  • While nonfunctional testing seeks to evaluate the performance of the software, functional testing aims to validate software actions.
  • The login functionality is an example of functional testing, whereas the dashboard should load in two seconds is an example of non-functional testing.
  • Functional and Non-functional define what the product accomplishes, whereas Functional explains how it operates.
  • Before the nonfunctional testing, functional testing is conducted.


Nonfunctional testing evaluates aspects of a program that don’t directly affect its functionality but are nevertheless crucial for the user experience. Although they aren’t essential parts of a software system, performance and reliability under stress can make or break the user experience.

Nonfunctional testing is carried out to confirm the application’s performance, usability, and other non-functional requirements. It checks to see whether the system is acting according to the specifications. It covers all the areas that functional testing does not.

They guarantee the software system’s dependability, availability, performance, and scalability. They aid in developing the software system’s security policy. They guarantee a positive user experience, make the product simple to use, and keep costs to a minimum.