What is Web App Testing—How to Test a Web Application?

We all use web applications daily - whether we're paying bills, purchasing groceries and clothes, booking flights for our next adventures, expanding our knowledge, learning new languages, watching our favorite movie or serial, and more. Nowadays, almost every task can be accomplished with a single “click”. However, to ensure this process is quick and smooth, each application must undergo extensive testing throughout its development across different environments. This is where web application testing comes into play.

In this article, we will cover all bases of web app testing, what it is, why it matters, how it differs from desktop app testing, some common challenges revolving around web app testing, plus the best tools to test your web applications. Let’s dive in.

What is web app testing?

Web app testing involves assessing and verifying a web application’s functionality, usability, security, and performance. It guarantees that the application functions correctly across various browsers, devices, and networks. This testing is essential for providing a smooth user experience and ensuring the application remains reliable under real-world conditions.

Web applications are programs that operate using servers and browser-based interfaces utilizing an internet connection to work. Many websites use these applications to provide specific services and features. They combine server-side scripts (such as Active Server Pages) and client-side scripts (like HTML) to present information to the users. For example, this could be in the form of an online flight ticket purchasing system. Typically, these applications require both application servers and web servers to function, and some may also need a database to store essential information.

Web applications are often complex, which creates numerous opportunities for bugs, glitches, and other errors to arise. Web application testing allows quality assurance teams and developers to gain a deeper understanding of the application and its functionality, including potential improvements. These tests assess various aspects of the application, such as performance, security, usability, and compatibility, to determine how well it operates. This involves evaluating both the backend and frontend of the program. By performing these tests, teams can ensure that the application is stable and ready for release, featuring all the necessary functionalities.

Web app testing vs. desktop application testing

Understanding the differences between web and desktop testing is crucial for ensuring the quality and reliability of software. In the following section, we will explore the major distinctions between web applications and desktop applications in terms of various parameters and how these differences influence the testing approaches for each.

Parameter	Web application Testing	Desktop application testing
Execution	Executes on browser, web server, and database	Executes on a single computer or workstation
Test environment	Web application testing is platform-independent and is conducted with the application running on a server accessible via web browsers like Chrome, Firefox, and Safari.	Desktop application testing is platform-dependent, requires different configurations for each supported platform, and is confined to the machine on which is deployed.
Deployment/upgrades	Deployments or upgrades are executed on a single set of server machines.	Deployment or any code upgrade needs to be done separately on all client machines.
Security	Web Applications are more prone to security risks due to their widespread accessibility. Security testing is a crucial quality assurance component, given the significant vulnerabilities to cyberattacks and other security threats. This underscores the need for thorough security testing.	Desktop applications, on the other, hand are better equipped in terms of authorization and administration control and are more secure. Hence, it requires minimal security testing or can be skipped.
Scope of testing	Includes testing for browser and OS compatibility, broken links, data volume, UI, and cross-browser functionality. Memory leaks and unhandled exceptions must be evaluated	Involves testing application features including GUI elements, backend database, and application load.
Storage of data	The data is stored remotely on the server and is accessed by our personal laptops remotely with the help of a web browser & internet connectivity.	Desktop applications store all the data on the machine on which the application is deployed.
Connectivity	Web applications rely on internet connectivity for proper functioning. Connectivity tests should be conducted to evaluate application performance at various speeds.	Desktop applications don’t require internet connectivity as they are hosted on the user machines only. Hence internet connectivity tests need not be in scope for these applications under test.
Accessibility	Web applications don’t have any location constraints to be accessed as they are deployed on servers that can be accessed from anywhere. Testing should involve different users testing the application from remote locations as well.	Desktop applications are confined to physical locations and hence can only be accessed from the machines on which they are inherently deployed. They can be tested only on the machine on which are deployed.
Number of users	Multiple users can access web applications across the internet and browsers.	At any given point in time, there is a single user testing or using the desktop application on a machine.

You might be interested in: The Ultimate Guide to Mobile App Testing.

Why is web app testing important?

Since web applications frequently act as the primary interface between businesses and users, their quality is of greatest priority.

Before the web application goes live or code changes are put into the production environment, web app testing checks for possible bugs. This is similar to editing an important email before sending it out. For example, you would verify that all of the links in the web application are operational, that the forms accurately submit data, or that the user interface functions as it should on various hardware and browser combinations.

The main goal is to deliver to the users a robust, secure, and user-friendly application, some of the benefits that web application testing offers are:

Increased user satisfaction. Ensures that the application is intuitive, simple to use, runs smoothly, and provides the necessary functionality. It usually involves testing the application from the user’s standpoint.
Functionality. Detects and fixes bugs or errors making sure every feature of the application works as intended. This is essential because nobody likes a broken login page or a malfunctioning shopping cart.
Improved security. In a world where data breaches are becoming all too common, a secure web application can be a significant competitive advantage. Web security testing protects sensitive data from vulnerabilities and breaches. A secure web application not only protects business data but also builds trust with the users.
Enhanced performance. One of the benefits of web application testing is enhanced performance, which is largely ensured through performance testing. Performance tests are designed to assess how a system behaves under a particular load, how quickly it responds, and how much load it can handle.
Compatibility. Confirms the application works across various browsers, operating systems, and devices.

When should you perform web application testing?

Web application testing should be conducted throughout the development lifecycle, starting from the early stages to ensure continuous quality. Key phases include:

During development. To catch bugs early through unit and integration testing, verify that different modules and third-party services integrate seamlessly.
Pre-release. Carry out comprehensive testing to ensure the app meets quality standards, and conduct end-to-end testing to evaluate the entire application’s functionality, performance, and security.
Post-release. Implement continuous testing to address user feedback and maintain performance.

How to test a web application?

Testing a web application involves various steps and testing types to ensure it meets all requirements. Effective web application testing can be performed if we follow these steps and common types of testing.

Requirement analysis. Understand the application’s purpose, features, and target audience. Review application specifications, user stories, and mockups to understand the testing scope. Identify critical features, user flows, and edge cases that need testing.
Test planning. Define the scope, objectives, tools, and types of tests to be performed. Identify test environments and data requirements. For example, plan to conduct functional testing on all major browsers, usability testing with target users, and load testing to assess performance under peak traffic.
Test case development. Create detailed test cases for different scenarios covering positive, negative, and edge cases. Specify clear preconditions, steps, input data, and expected results for each test case. Develop test scripts for automation using frameworks.
Environment setup. Configure the testing environment to simulate real-world conditions like necessary hardware and software testing tools. Set up test environments mirroring production, including servers, databases, and configurations. Ensure that test data is available and properly anonymized.
Test execution. Run the prepared tests against the web application and document results in a defect tracking system, including reproduction steps and severity. Record actual results and compare them with expected outcomes. Log any failures, errors, or discrepancies encountered.
Defect reporting. Log and prioritize issues for resolution. Collaborate with developers to troubleshoot and fix identified defects. Update defect status and maintain a clear audit trail.
Retesting and regression testing. Verify fixes and ensure new code doesn’t impact existing functionality.

What are some web application testing types?

These are some of the fundamental web application testing types:

Functional testing

Functional testing verifies that all features and functionalities of web applications operate in conformance with the required specification. It ensures that the functionalities and requirements work from the end user’s perspective This includes black box techniques like boundary value analysis (testing the boundaries of input fields) and Equivalence partitioning (dividing input data into equivalent partitions and testing them) as well as using test cases based on specifications and user stories

Example: Form and link validations, database interactions, cookie testing, and navigation.

Usability testing

Usability testing assesses the user-friendliness and design of the application. Usability testing follows established practices to ensure that a web app is easy to use, effective, and flexible in handling controls while meeting its intended objectives. This process identifies errors such as typos, punctuation issues, and unclear flow to promote a positive user experience. Common methods for conducting usability tests include user interviews, surveys, and usability sessions where testers observe real users interacting with the app.

Example: Intuitive layout and accessibility for all users.

Performance testing:

Performance testing evaluates the app's speed, scalability, and stability across various scenarios. It evaluates whether the system can maintain consistent efficiency while handling outputs from different users. Performance testing ensures that the architecture can support heavier loads, provide fast response times with each software update, and effectively manage maximum load conditions to deliver optimal performance.

Example: Load testing to handle concurrent users.

Compatibility testing

Compatibility testing ensures the app works seamlessly across different browsers, devices, and operating systems. It's about providing a consistent user experience regardless of the platform. One of the most used techniques for compatibility testing is cross-browser testing besides responsive design testing, emulators and simulators, and manual testing on actual devices and browsers

Example: Operating system compatibility or mobile browsing.

Security testing

Security testing identifies vulnerabilities and ensures data protection on web applications. Security testing serves several important functions, including: preventing unauthorized access to secure pages, stopping the downloading of authorized pages without approval, terminating automatic sessions after prolonged user inactivity, redirecting the website to encrypted SSL pages, and verifying CAPTCHA to block automated script logins.

Example: Penetration testing and authentication checks.

Accessibility testing

Accessibility testing ensures the application is usable for individuals with permanent or temporary disabilities, including visual, auditory, motor, or cognitive impairments, by adhering to standards such as WCAG. This helps organizations expand their user base, comply with legal requirements, and enhance the overall user experience.

Example: Test the web application’s compatibility with screen readers, ensure proper alt text for images, and check for sufficient color contrast.

Challenges of web application testing

Testing web applications comes with several challenges due to their dynamic nature and the complexity of modern technologies. Some of them are:

Cross-browser and cross-device compatibility. Ensuring consistent functionality and appearance across various browsers (e.g., Chrome, Firefox, Safari) and devices (desktop, mobile, tablet) is challenging due to differences in rendering engines and capabilities.
Dynamic and responsive design testing. Testing applications with responsive designs is crucial to ensure optimal usability across various screen sizes. A tester must check for issues such as horizontal scrolling, alignment, padding, and the sizes of fonts and buttons on different devices. This process can be time-consuming and may require specialized tools
Security vulnerabilities. It's crucial to be sure online apps are secure, given the increase in cyberattacks. Identifying and addressing security threats such as SQL injection, XSS, and data breaches requires constant carefulness and specific expertise and equipment.
Performance under load. Ensuring optimal performance is crucial for retaining users and maintaining their satisfaction. Simulating high user loads and ensuring the application’s performance under stress can be difficult, especially for global applications with varying traffic patterns
Environment and network constraints. Testing the application’s performance and functionality on various network conditions and environments (e.g., slow connections, and offline modes) can be inconvenient.

Web application testing tools

Web application testing tools are crucial for ensuring software quality and reliability. They help identify bugs, provide feedback about their occurrences, and facilitate their resolution before the application is deployed to production.

These tools are essential for automating many repetitive and time-consuming tasks, which reduces manual effort in QA processes. Additionally, they minimize the occurrence of errors and human fatigue, thereby streamlining bug tracking and resolution.

Various tools can assist in different aspects of web application testing. Here are a few:

Functional testing: Selenium, TestComplete
Performance testing: Loadero, JMeter, LoadRunner
Usability testing: Crazy Egg, Hotjar
Compatibility testing: BrowserStack, Sauce Labs,
Security testing: OWASP ZAP, Burp Suite

When selecting the right tools, developers and engineers must carefully assess their requirements before deciding which options best suit their project, skills, or technologies.

Final thoughts

Effective web app testing is not just a phase in the development process, it is a crucial foundation for creating successful, user-friendly, and reliable applications. By following a systematic approach and utilizing modern testing tools, web applications meet the required quality standards, providing users with a seamless and secure experience. Additionally, testing is vital for maintaining a business's reputation, as the quality of a web app directly affects user satisfaction and engagement.

Ready to launch your web application? Reach out and learn how our web app testing services can help you deliver safe, reliable, and bug-free solutions that users will love.