Automated Functional Testing — How To Do and Best Practices?

April 19, 2024Adhithi
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No matter the codebase or structure, there’s just so much to do when it comes to testing. From validating the unit code and integrated modules to running regression tests and acceptance testing for the complete system, functional testing covers everything. Naturally, it would take a ton of time if done manually. Fortunately, much of the world has moved on to automated functional testing to make the process effortless, less time-taking, and still accurate. 

That’s what we’ll be focusing on today. Along with the logistics of functional testing, we’ll learn the approaches to automated functional testing and look at the tools at our disposal. Let’s get started.

What is Automated Functional Testing?

Functional testing refers to verifying the functional aspects of a software application. It includes features, such as login, search function, clickable elements, and many more interactive pieces present on the web page.

Think of it like this — the software you develop has many set requirements for functionality. For example, a specific interaction with the UI would result in a certain change. Functional testing primarily ensures that each of these parameters work flawlessly. Programmers even refer to “Functional Testing” as a black box test (although that’s not all it is). That means you are primarily concerned with the software’s input and output. What goes on in between is not a huge concern.

Functional Testing

Automated Functional Testing — When Functionality Meets Automation

As you’ve noticed (or worse — experienced) by now, functionality tests can be pretty tedious. And if you’re constantly churning out new builds and commits to the code, it can become more complex to manage. 

The essence of automation functional testing lies here — automating any step you often repeat to make things faster and more efficient. It’s designed according to the program’s needs so that the workflows can differ from each other.  

The question is whether you can justify re-designing your whole test script and automating it. After all, it will initially take a bit of an overhaul. 

In short, yes. Here’s the broader version:

Benefits of Automation Testing

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Time Efficiency 

The first benefit of automation is that you save a ton of time. Let’s say the development team just committed a new feature to the code. Suffice to say that manually testing the software after each change will be a chore and a half. 

With automation, you can cut down on time needed to make those tests. It’s also easier to validate each build and quicken the feedback cycle.

Cost Efficiency

Along with time comes the aspect of cost. Basic math says that the more time testing takes, the more money we burn in logistics. Automated tests take much less time (especially if the tests are repetitive, which they typically are). Hence the process spends fewer resources on it. 

Surely, the automation process will take resources. But as you keep utilizing it, again and again, that cost seems measly compared to what it would be with manual tests. 


The modularity and reusability of these tests are amazing. If you design the test for a program, you can keep using it for most of that program’s lifetime without any issue. And secondly, you could also utilize parts of it for other programs, depending on how many similarities they share. 

Fewer Human Errors

Manual testing is prone to human errors. And it would always be because no matter the experience, humans can commit mistakes. But the issue is that it skews the results. Automated Functional testing aims to ensure that there are no flaws from the test’s side of things. That way, it can ensure consistency and create a better output. 

Test automation eliminates the chances of skewed results in your development. You’d be reusing the same code and preventing unaccounted flaws from the test. 

Accurate Insights 

From the previous point comes the accuracy of insights. For example, let’s say that a certain part of the UI failed to function as intended. On an automated test, the insights would contain every little detail and categorize them in a manner that makes problem-solving infinitely easier. You could easily look at all of the variables and catalysts that resulted in the error and resolve the issues. 

Feature-Rich Test Designs 

When doing things manually, there’s a limit to how much you can work without wasting a lot of time and resources. That reduces the efficiency of the test, as we wouldn’t get to try out all of the scenarios. 

Automation broadens the horizon here. You could emulate all sorts of scenarios without having to worry about the logistics behind them.

As you can see, automation barely has any significant drawbacks when done right. However, the question is whether automating every bit of the process is rational or not.

Which Parts of the Functional Test Should You Automate?

Here’s the thing — automation takes a decent chunk of resources, at least in the initial stage. Not every part of it would be cost and time-efficient. How do you determine which elements to automate, then? Here’s a short checklist that can help. 

Any test that you perform again and again can and should be automated. The reasoning is simple — automating the test once would save you from manually repeating all of these tests repeatedly.  

Then, there are some tests that require more work from the tester. Not only are these tedious, but the chances of human error are usually higher. Automating these tasks makes sense and can make things convenient in the long run. 

Many of our tests run on multiple operating systems, platforms, or browsers, depending on the program you’re developing. That means the same functional tests must run on each of them, taking up a lot of time. These are suitable cases for automation and are easier to scale.

Different Tools Used for Automating Functional Testing

Much like how each software requires a different testing path and methodology, automated functional testing software also varies depending on the use case. Here are some of the tool options you’ll come across. 


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We couldn’t leave our brainchild out of the equation, could we? So the USP of Testsigma is simple! The tool is cloud-based and allows access to its NLP list anywhere, everywhere. It works with web apps, mobile apps, and API tests. That’s helpful if you have your product on multiple tech stacks and are testing all of them.

Support for different operating systems and browsers is also present, along with the capability to provide continuous feedback. This capability is helpful, especially when you’re committing changes and want to check whether everything is working properly.

And given that it can efficiently run tests in parallel, developers can save a lot of time without waiting for threads to finish up. Then comes the insight, arguably one of the best things about automating tests with Testsigma. Everything is presented with easy-to-understand timelines and reports within short and long intervals.

Moreover, the overall integration of this suite (through the software development kit and APIs) seemed pretty smooth. That smoothness improved even more with the utilization of additional plugins like data generators from its extensions/add-ons collection. 

Automate your functional tests, 5x faster, with Testsigma [Check out Testsigma]


No matter where you go, Selenium is a name you’re bound to hear for automated functional testing. This open-source program is primarily designed for web apps and has been around for a long time. 

As expected, it supports most mainstream operating systems and browsers — from Linux, Windows, to Chrome and Edge (and the good-old IE — RIP). You can also write the tests in a bunch of languages, depending on your preference. The options include Java, Python, C#, PHP, and many more. 

Creating tests on this is fairly intuitive, and the whole thing becomes much more effortless given how long it has been around. 


This is a testing software developed by SmartBear, which is rather powerful and versatile. For one, it comes with a prebuilt test editor for keyword-driven workloads. It supports languages like C#, JS, Python, and C++Script.

It covers a plethora of tests including unit testing, coverage testing, data-driven testing, regression testing, and many more. Another impressive bit is that it utilizes AI to recognize UI elements. Having such capabilities reduces the load on the tester.  

What I like about this tool is its impressive continuous testing capabilities. Users can integrate it with all sorts of frameworks, ranging from Jenkins to Jira. And as expected, cross-browser testing is as good as it gets when it comes to testing web apps. 


Certify is a robust testing software designed by Worksoft. It works flawlessly on multiple platforms and operating systems. The best thing is even large-scale software developers rely on it, meaning the scalability and capability of this tool are beyond doubt. Even large enterprise applications like Oracle utilize it.  

The setup process and design are rather intuitive, and it supports all of the common testing methodologies. Moreover, this tool works exceedingly well if your testing team includes non-technical people in it. Users can write codeless tests with it, which allows everyone to play a role. 

However, it may not be the ideal way to go for small-scale applications. The biggest reason behind that would be its price, which may not be feasible unless you have got a comparatively large-scale application. 

Unified Functional Testing (AKA UFT)

UFT is one of the most popular tools utilized for functional test automation across multiple platforms and environments. This tool also features a quality object recognition capability, which reduces the load on your shoulders. 

It works on a wide array of elements including APIs, mobile, desktop, and web apps and services. You could use this to run through the interface and both the service and database layers efficiently. This is not an open-source tool, so you’ll have to purchase the license. 

The insights that it presented were easy to figure out and utilize to create swift decisions, cutting time off the testing process. 


Here’s another GUI testing tool for the trio of desktop, mobile, and web applications. This is an excellent solution if you require continuous tests during your development cycle. That also means you’ll get quick feedback to get things running swiftly. 

Another benefit of Ranorex is its intuitiveness. You can even take a no-code approach with this tool, which is especially beneficial for beginners. It also has support for all of the major platforms and browsers for cross-browser testing. 

What this automated functional testing tool excels at is its object identification capability. For example, if you make changes to an element on the user interface, Ranorex will be able to update that repository accordingly without any intervention from the testers. 

Moreover, it comes with a video reporting capability. That way, users can rewatch the whole test without actually running it. This certainly saves users time and resources. 


Here’s yet another open-source automated Functional testing framework. It’s primarily developed with Java and Swing. While Marathon is better suited for smaller applications, it has another version (MarathonITE) to work on larger and more complex programs. The environment is well-integrated and makes test automation straightforward, even for beginners.  

Sauce Labs

Another efficient tool for tasks like continuous testing would be Sauce Labs. What makes it unique is its cloud-based testing design, which gives you an edge for frequent tests. 

It also comes with a low-code testing capability, meaning you can write the test script without any programming language. That’s pretty handy if you’re new to automation tests. Furthermore, the insights and reports are well-detailed and helpful. It also works with Selenium, Appium, and even Playwright.  

How to Design Automated Functional Tests?

So, now we want to design and automate a functional test for our program. There’s no ideal path to do that, per se. We have too many variables to create a one size fits all pathway. Nevertheless, here’s a good way to get started with automation testing. 

1.Determining What to Test and Which Approach to Adopt

Be it a few people or a large QA team, the goal remains the same — making the software as functional as possible and as efficiently as we can. To achieve that, the first step would be to determine which parts of the software or program you want to test.

You’ll sometimes find that not all of the bits need to be automated, especially if you’re only going to run them a handful of times. It makes more sense to run them manually in those cases instead of wasting time on automation. 

Part of this decision will depend on which stage of development you’re in. For instance, you’d only focus on some specific functions if only a part of the program received changes. Moreover, it can depend on the type of functionality test you’re running (and many other variables). 

Here are some methodologies that you might adopt: 

Keyword-Driven Tests

Keyword-driven testing (some call it action word-based) enables you to separate the test designing from test development. This is quite common with testing teams nowadays, where not all of the testers are adept at scripting languages. 

If your QA team includes non-technical people, a keyword-driven test can be beneficial. These tests necessitate in-depth planning before you move on to the actual testing and development. 

Data-Driven Tests

Data-driven testing relies on a set bunch of data from your database instead of some set codes. The best thing is that these don’t need anything other than your data and the test script to run, which makes test designing more convenient. 

That means these can take less time compared to keyword-driven tests. These tests also reduce the possibility of errors. However, they are trickier to manage, especially for non-technical people. 

Modularity-Driven Tests

As the name suggests, you can create a modular test script, where there are a bunch of automated testing scripts for the application. Testers can then set the overall execution pattern and have the test work as a whole. The best thing about these tests is that they’re far easier to maintain. 

They also make it effortless when you’re working as a team on testing a program. It’s also possible to combine these modules to create different tests, and complex programs can benefit from them. 

You can determine the suitable methods for your programs depending on your requirements.

2.Choosing an Automated Functionality Testing Tool

Once the path to follow has been chosen, the next step is to select the tool to create it. There are now hundreds of automated functionality testing tools on the market, but only a handful would fully suit you. So, what should you consider in that case?  

Firstly, determine whether your QA team is capable of coding the test scripts out. If you’ve only got coders as testers, then you have to look at which languages the tool supports, and so on.  

Then comes the question of compatibility. For one, the language you’re using to write the software is crucial. The platform your software is designed for (e.g., for Android or browsers, or for Windows) is also essential to look at. Not every tool would be great at something like web applications or Android apps and vice versa. 

Reusability of the code is another aspect to consider, as that can save a lot of energy. How it reacts to changes made in the UI or the test’s codebase is also a question we should ask. And if you need specific testing capabilities (let’s say Record & Playback tests), check if that Automated Functionality testing tool can accommodate those proficiently. 

3.Defining What Counts as Successful 

Each test has a standard is determined to consider if the test ran successfully (also known as Definition of Done). Consequently, these standards are up to the testers to design and place. You could call an 8% success rate your definition of done, which would technically keep up with the standard. 

That’s why it’s essential to write tests with the proper standards in mind. This is even more crucial when you’re working as a team. For example, maintaining a high accuracy rate or utilizing things like POPs (page object patterns) from the start should be a necessity. 

Keeping the code clean and non-repetitive, ensuring the test fulfills all of the criteria before you call it a day — things like these aren’t challenging or unreasonable. Therefore, we should ensure that they’re a requirement right from the start. 

4.Writing the Automated Tests

Now, how we write the tests depends on a whole range of factors. The tool in use, the language we’re writing the tests in, the type of software we’re testing, the type of tests we’re scripting — the list does not end. And since none of us wants to stay here all day, let’s not go down that path. 

However, there are some things you should remember while scripting for the best output. As an example, a data-driven test should be written to maintain its modularity. Modularity would allow for great things since the test itself can be used against different data sets without changing anything. 

Another bit is writing the code (it could be a no-code tool as well) so that any changes in the UI won’t affect anything. Poorly-written tests often suffer because any minute change to the UI ends up breaking things. Iteratively scripting the tests is a great idea to keep things easy to fix and straightforward. 

It’s also essential to keep the tests efficient so that you don’t spend ages on a single test. That’s not the ideal case scenario if we want to maintain a high ROI. Many people also overlook that unit tests can be easier to write and fix instead of complex stuff. Utilizing these while scripting can help the ROI and keep the people above happy. 

Limitations of Automated Functional Testing

Functional automation testing sure has its perks, like speed and repeatability, but let’s not overlook its limitations. 

Firstly, setting up and maintaining those automated test scripts can be quite the investment, both in terms of time and resources. And when it comes to complex user interfaces or dynamic web apps, automated tools might struggle to mimic real user behavior accurately. 

Then, there’s the issue of missing those subtle defects or corner cases that a human tester might catch. 

Furthermore, automated tests may become brittle and require frequent maintenance as the software evolves, which might lead to increased maintenance costs and efforts. Not to forget that automated tests may not effectively detect visual defects or issues related to usability and accessibility, as they primarily focus on functional correctness.

How to Perform Automated Functional Testing Using Testsigma?

Let’s consider an example where you have to test the search functionality of Simply Travel website.

Follow the below steps to validate the function using Testsigma.

Step 1: Log into the Testsigma Cloud and click on Create Tests -> Test Cases

1.automated Functional Testing Using Testsigma

Step 2: Give the test case a name and start creating test steps. You can either select the pre-defined NLPs to create test steps manually or record and play the steps.

2.automated Functional Testing Using Testsigma

Step 3: Once, all the test steps are done. Run the test case and see if it passes or fails.

Configure the test.

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Run the test steps.

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Step 4: Report and analyze the test results using screenshots and results logs.

5.automated Functional Testing Using Testsigma

Step 5: Verify that the search function displays the list of flights when the To, From, and Travel dates are filled properly.


Functional testing is a tough cookie to crack, and the logistics aren’t easy to maintain. So it’s only natural for the world to swiftly move on to automated functional testing. 

And I realize that it’s a vast arena — one that we can’t entirely cover in one article. Nevertheless, this piece should be a helpful stepping stone if you want to learn automation testing and figure out the right path to follow. 

Don’t overlook the actionable benefits and possible challenges you might have to encounter. But the list of tools is available for you to decide and select which platform works the best for you.

Frequently Asked Questions

What tool can be used to automate functional testing?

More than one perfect tools exsit for you to run functional test automation. Some are around since long and have garnered a loyal customer base. Others have come up in recent times by embracing new technology, such as AI and NLPs.

Testsigma is a low-code, cloud-based functional test automation tool that supports end-to-end testing for web applications, mobile applications, and APIs. It is capable of handling complex test cases and functions for small and large applications.

On the other hand, if your team is looking for something robust that allows you to create code-based test scripts, choose Selenium or a similar tool.

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