Functional testing comes in all shapes and sizes, and the same goes for functional testing tools.
I’ve reviewed and evaluated the most popular functional testing tools and shortlisted the best ones for your QA team to improve software quality and increase testing efficiency.
When it comes to functional testing (or just any types of testing), QA teams usually have up to 3 options, with increasing levels of scalability:
One option for your team is to use an open-source testing library as the foundation for your custom testing framework. This core library will provide essential testing features, and you can build additional layers to make the framework more user-friendly and flexible.
The building blocks of a testing framework include:
If you choose this route, you’ll need strong coding skills to connect these components and create a framework that simplifies testing.
Pros:
Cons:
Building your own framework gives you more control but requires significant effort to set up and maintain. While it’s cost-effective, the maintenance phase often takes the most time, especially when managing large test suites.
These are commercial tools i.e. you have to shop around for a suitable one and invest a certain amount to get access to the features. As their name suggests, these tools only have to meet a single testing purpose, and we can categorize them based on the purpose they serve:
For example, Postman’s focal point is solely on API performance, security and functionality. If APIs are at the top of your testing list, give it a go. While it is indeed nice to have a tool solely dedicated to a part of your functional testing, there will come a point when you want to have a more comprehensive testing experience. After all, the dedicated nature of these tools also limits their potential for expansion and scaling.
📚 Read More: Top 15 Postman Alternatives You Should Consider For Your Team
In other words, single-point commercial automation testing tools are amazing if your organization only needs to test within the features of that tool. However, as the team scales, and you want to branch out further to test other areas of the software, it is better to go with an entire software quality management platform.
A software quality management platform incorporates all functionalities needed to automate and view the full picture of quality activities. In a way it is several single-point commercial automation testing tools unified into one, carrying all of the features that the team potentially need.
Software quality management usually includes several connected stages, from planning to reporting. Using separate tools for each stage often leads to a scattered view of quality, where teams waste time trying to piece everything together.
The real value of modern testing platforms is that they give teams an all-in-one workspace. You can test web, API, and mobile-native apps using a shared keyword library. Tools for linking requirements, writing automation scripts, and tracking test coverage are built in, so there's no need to search for or connect extra tools.
To give a non-biased list of tools for automated functional testing, a mix of open-source libraries and vendor solutions are listed below.
Katalon is a true all-in-one automated functional testing tool. With a Katalon license, you can:
Katalon is also one of the first AI-powered automation testing tools. Notable features include:
Watch this video from Daniel Knott, one of the most popular software testing influencers, to see Katalon AI in action:
Are you ready for an upgrade of your functional testing?
Visit Katalon Website | Pricing | G2 Reviews
📝 If you want a more customized automated functional testing tool for your team, you can request a demo from Katalon here.
Selenium is a suite of libraries and extensions used to build a framework to automate the testing of web applications.
Actions users take on web apps — clicking buttons, scrolling, entering usernames/passwords — are replicated by Selenium interacting with browser drivers.
Feature highlights:
Cypress is not new to front-end developers using TDD/BDD for JavaScript-based frameworks. With Mocha as its underlying framework, Cypress focuses on solving wait and timing issues present in Selenium WebDriver.
Feature highlights:
Visit Cypress Website | G2 Reviews
Pricing: Free tier available. Paid plans start at $67/month; Enterprise tier offered.
📖 Read More: Katalon vs Cypress: A Detailed Comparison
Built by the original Puppeteer developers, Playwright expands cross-browser support for automated web testing. It provides APIs to interact with Chromium, Firefox, and WebKit using JavaScript.
Feature highlights:
Visit Playwright Website | G2 Reviews
Pricing: Open-source
Appium is a Node.js library used to build testing frameworks for native, web, and hybrid mobile apps. It uses Selenium WebDriver and JSON protocols to drive iOS and Android applications.
Many language bindings already exist, so getting started is easy without writing everything from scratch. Appium includes strong gesture and touch automation capabilities for complex mobile interactions.
Feature highlights:
Visit Appium Website | G2 Reviews
Pricing: Open-source
Tricentis Tosca is a comprehensive automation tool designed for large-scale UI and functional testing across web, API, mobile, and desktop applications. It uses a model-based testing approach to map UI or API behavior into reusable test models that reflect real business workflows.
Highlight features:
Visit Tricentis Tosca Website | G2 Reviews
Pricing: Contact sales
TestComplete is a robust automated functional testing tool designed for conducting functional UI testing across desktop, mobile, and web applications. It supports over 500 native controls and works with third-party frameworks, allowing it to effectively interact with dynamic UI elements across many technologies.
Highlight Features:
Visit TestComplete Website | G2 Reviews
Pricing: 14-day free trial. Paid plans: Fixed and Floating licenses.
Karate DSL is designed for both non-technical users and developers to test APIs using BDD scenarios. Built on Gherkin, it removes the need to write extra Java step definitions, keeping test code shorter and easier to maintain.
Feature highlights:
Visit Karate Labs Website | G2 Reviews
Pricing: Open-source
Rest Assured is a Java library for testing REST APIs and RESTful (XML/JSON) web services. Like Karate DSL, it supports Given-When-Then syntax while allowing further customization using Java.
Feature highlights:
Website: Rest Assured
Pricing: Open-source
XCUITest was built for iOS developers. As a sub-framework of XCTest, it allows users to validate mobile UI behaviors using test classes, methods, and test targets.
Feature highlights:
Pricing: Open-source
With all of the functional testing tools listed above, you can now start improving your testing activities and streamlining the entire process:
Examining if an application works as expected takes tremendous time if done manually. While manual testing still plays a role (e.g., user acceptance testing), reusable automation scripts drastically shorten testing cycles.
Tests that are best suited for automation include:
Software quality is a shared responsibility. From functionality and security to performance and usability, both developers and quality engineers contribute to ensuring testability.
Developers write unit tests early to prevent dependency complications.
Quality engineers extend coverage using methodologies like behavior-driven development (BDD) and data-driven testing (DDT).