There are several ways to test the functionality of a website during development. Here are some common methods:

1. Manual testing: This involves manually going through the website and testing each feature to ensure it works as expected. You can create a checklist of features to test and record any issues you encounter. This method can be time-consuming but can help you catch issues that automated testing may miss.
2. Automated testing: This involves using automated testing tools to run tests on your website. You can write scripts that simulate user interactions and test various features of your website. Automated testing can be more efficient than manual testing, but it requires some technical skills to set up and maintain.
3. Cross-browser testing: It's important to ensure that your website works well on different browsers and devices. You can use tools such as BrowserStack or Sauce Labs to test your website on various browsers and devices without having to set up each one manually.
4. Load testing: This involves testing how your website performs under heavy traffic. You can use tools such as LoadNinja or Apache JMeter to simulate high traffic on your website and see how it handles it.
5. Accessibility testing: It's important to ensure that your website is accessible to people with disabilities. You can use tools such as Wave or Axe to test the accessibility of your website and make sure it meets the WCAG 2.1 guidelines.
6. Code review: Another way to test the functionality of your website is to review your code. You can use tools such as CodeClimate or SonarQube to analyze your code and identify any potential issues or bugs.

It's important to test your website regularly during development to catch any issues early on and ensure a smooth user experience.

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Starting With Selenium

First, you need to analyze the application you want to automate. Next, you should know whether you want to do it with record and play or writing robust, browser-based regression automation suites and tests.

If you don’t need a full-fledged framework and if the tests which you want to automate are quite simple then you can go for record and play feature of Selenium IDE. It is implemented as Chrome and Firefox Extension. It has intelligent field selection which can identify an element using ID, Class and Xpath.

• Creating WebDriver Instance:

You need to create Webdriver instance. You can make a reference of WebDriver and you can have child object of its implementation classes like GoogleChrome, Internet Explorer or others.

WebDriver driver= new FirefoxDriver();

WebDriver driver = new ChromeDriver();

WebDriver driver = new InternetExplorerDriver();

Also, keep in mind that if you are using ChromeDriver and InternetExplorerDriver then you need to set path for their executable file with the help of System.setproperty.

System.setProperty(“webdriver.chrome.driver”, “Path”);

System.setproperty(“http://webdriver.ie.driver”,”Path”);

You don’t have to set it for firefix but if your selenium version is above 3.0 then you need to set path of gecko driver in your code.

System.setProperty(“webdriver.gecko.driver”,”Path”);

• Navigate To Webpage Which You Want To Test:

After making instance of webdriver now it is time to actually open the web application which you want to test. You can navigate to webdriver using get or http://navigate.to.URL() function.

driver. get(“URL”); // This will land you to our webpage which you want to test.

• Locate an HTML Element on Webpage:

After you have landed on the webpage you can now interact with the webpage using HTML elements. There are many locators which you can use to find out the elements. They are name, class name, Xpath, CSS and ID. You can take help of firebug or developer tools to find out your desired element.

WebElement login = driver.findElement(Domain Premium: By.id(“”)); // one example of locator

• Perform an Action on WebElement :

When you have found web element, now comes turn to do some action on it. For example if it is username you can enter words from keyboard and if it is login button, you simply have to click on that.

username.sendKeys(“”); // for sending input from keyboard to username textbox

login.click(); // for clicking on login button

• Anticipate The Browser Response to the Action:

Browser takes some time to actually load the page. You should have some default time wait for all the web elements till the life time of driver instance. This can be done by implicit wait in Selenium.

driver.manage().timeouts().implicitly Wait(10,TimeUnit.SECONDS) ;

This time would be applicable for all web elements. But sometimes there is a situation when only one element takes longer time to load then in such cases you can use explicit wait.

WebDriverWait wait=new WebDriverWait(driver, 20);

wait. until(ExpectedConditions.visibilityOfElementLocated(By.xpath(“”)));

You can have N number of conditions with wait object.

• Close Browser Session

You can close the browser the required test is performed.

driver.close(); // will close the current session

• Run Tests and Record Test Results Using a Test Framework

Whatever I have explained till now will help you to run a single test. You can even maintain a framework to run test suites with beautiful report generation. You can take help of Maven, POM and TestNG to make such a robust framework.

Have a look on this page for more details: Cross Browser Testing using Selenium Automation

Testing is probably the most routine part of a process. Every single link should be tested to make sure that there are no broken ones among them. You should check every form, every script, run a spell-checking software to find possible types. Use code validators to check if your code follows the current web standards. Valid code is necessary, for example, if cross-browser compatibility is important for you.

After you check and re-check your website, it’s time to upload it to a server. An FTP (File Transfer Protocol) software is used for that purpose. After you deployed the files, you should run yet another, final test to be sure that all your files have been installed correctly.

Basic steps followed in companies:-

1. Functionality Testing
2. Usability testing
3. Interface testing
4. Compatibility testing
5. Performance testing
6. Security testing

1. Functionality Testing

Test for – all the links in web pages, database connection, forms used in the web pages for submitting or getting information from user, cookie testing.

2. Usability Testing

Navigation means how the user surfs the web pages, different controls like buttons, boxes or how user uses the links on the pages to surf different pages. Generally usability testing includes -

Web site should be easy to use. Instructions should be provided clearly. Check if the provided instructions are correct meaning whether they satisfy the purpose. Main menu should be provided on each page. It should be consistent. Content should be logical and easy to understand. Check for spelling errors. Use of dark colors annoys users and should not be used in site theme.

3. Interface Testing

The main interfaces are:

• Web server and application server interface
• Application server and database server interface

Check if all the interactions between these servers are executed properly. Errors are handled properly. If database or web server returns any error message for any query by application server, then application server should catch and display these error messages appropriately to users. Check what happens if user interrupts any transaction in-between? Check what happens if connection to web server is reset in between?

4. Compatibility Testing

Compatibility of your web site is very important testing aspect. See which compatibility test is to be executed:

• Browser compatibility
• Operating system compatibility
• Mobile browsing
• Printing options

Browser Compatibility

This is the most influencing part on web site testing. Some applications are very dependent on browsers. Different browsers have different configurations and settings that your web page should be compatible with. Your web site coding should be cross browser platform compatible. If you are using JavaScripts or AJAX calls for UI functionality, performing security checks or validations, then give more stress on browser compatibility testing of your web application.

Test web application on different browsers like Internet Explorer, Firefox, Netscape Navigator, AOL, Safari, Opera browsers with different versions.

OS Compatibility

Some functionality in your web application may not be compatible with all operating systems. All new technologies used in web development like graphics designs, interface calls like different APIs may not be available in all Operating Systems.

Test your web application on different operating systems like Windows, Unix, MAC, Linux, Solaris with different OS flavors.

Mobile Browsing

This is the new technology age. So in future, Mobile browsing will rock. Test your web pages on mobile browsers. Compatibility issues may be there on mobile.

Printing Options

If you are giving page-printing options, then make sure fonts, page alignment, page graphics are getting printed properly. Pages should fit to paper size or as per the size mentioned in the printing option.

5. Performance Testing

Web application should sustain to heavy load. Web performance testing should include:

• Web Load Testing
• Web Stress Testing

Test application performance on different internet connection speed.

In web load testing, test if many users are accessing or requesting the same page. Can system sustain in peak load times? Site should handle many simultaneous user requests, large input data from users, simultaneous connection to DB, heavy load on specific pages etc.

Stress testing: Generally stress means stretching the system beyond its specification limits. Web stress testing is performed to break the site by giving stress and checked how system reacts to stress and how system recovers from crashes.

Stress is generally given on input fields, login and sign up areas.

In web performance testing web site functionality on different operating systems, different hardware platforms are checked for software, hardware memory leakage errors,

6. Security Testing

Following are some test cases for web security testing:

• Test by pasting internal URL directly into browser address bar without login. Internal pages should not open.
• If you are logged in using username and password and browsing internal pages, then try changing URL options directly, i.e., If you are checking some publisher site statistics with publisher site ID= 123. Try directly changing the URL site ID parameter to different site ID which is not related to logged in user. Access should be denied for this user to view others stats.
• Try some invalid inputs in input fields like login username, password, input text boxes. Check the system reaction on all invalid inputs.
• Web directories or files should not be accessible directly unless given download option.
• Test the CAPTCHA for automates scripts logins.
• Test if SSL is used for security measures. If used, proper message should get displayed when user switches from non-secure http:// pages to secure https:// pages and vice versa.
• All transactions, error messages, security breach attempts should get logged in log files somewhere on web server.

How to Perform Accessibility Testing of Websites

Accessibility testing ensures your website is usable for people with disabilities, adhering to standards like WCAG (Web Content Accessibility Guidelines). Below are the steps to perform accessibility testing effectively:

Steps for Accessibility Testing

1. Understand Accessibility Standards Familiarize yourself with WCAG, Section 508, or other relevant guidelines. Ensure your website meets Level A, AA, or AAA compliance.
2. Automated Accessibility Testing Tools Use tools like Axe, WAVE, or Lighthouse to analyze your website for common accessibility issues. Tools identify issues like missing alt text, color contrast problems, and more.
3. Keyboard Navigation Testing Test navigation using only the keyboard. Ensure all interactive elements, like buttons, links, and forms, are accessible via Tab/Shift+Tab keys.
4. Screen Reader Testing Use screen readers like JAWS, NVDA, or VoiceOver to verify that content is read out correctly and navigation is intuitive.
5. Mobile Accessibility Testing Test on mobile devices to ensure accessibility features like zoom, screen readers, and gestures work seamlessly. Tools like HeadSpin can help test mobile accessibility across devices.
6. ARIA Roles and Landmarks Ensure correct use of ARIA (Accessible Rich Internet Applications) roles to improve compatibility with assistive technologies.
7. Color Contrast and Visual Design Check color contrast ratios using tools like Contrast Checker to ensure text is readable for visually impaired users.
8. Manual User Testing Involve real users with disabilities to test your website and provide feedback.

HeadSpin’s Role in Accessibility Testing

• Real Device Testing: HeadSpin enables testing on real devices to ensure consistent performance across different platforms and environments.
• AI Insights: Provides actionable data on accessibility issues like loading times, screen layout, and usability across devices.
• Comprehensive Testing: Simulates diverse network conditions and geographies for globally accessible user experiences.

By combining automated tools, manual testing, and HeadSpin’s advanced testing capabilities, you can deliver an inclusive and accessible web experience.

Test Your Website

What is the single most important thing to do beyond creating a website? It’s testing it. There are any number of ways that a website can be tested to ensure that you are doing what you can to reach your target audience, enhance sales and provide your readers with what they need to stay loyal to you. So, let’s get to work.

Before You Go Live

Some aspects of your website always need to be examined and re-examined. It is the curse of good, the enemy of better. But, readers like to know that you pay attention to detail and here is where it all comes together. You have sent out press releases, announced that you will be unveiling a website for your business or other organization. People are waiting with expectancy, so don’t disappoint them if you can help it.

Here are some areas to pay special attention to before the big launch day.

1. Check for typos and other errors – If you don’t check and recheck, you are guaranteed to miss something. Ask a friend to read over your pages as a fresh set of eyes. This includes site maps, buttons, headers and the like.

2. Check your forms – Do they appear as they should? Do all the boxes work? Is it easy to navigate? Does it direct the customer to the right landing page when they hit “continue?”

3. Check page loading times – The kiss of death is that spinning wheel that signifies something is possibly going on in the background although you don’t know what. Ensure that loading speeds for pages are inside acceptable parameters. If they are loading slowly, there is a problem that needs attention.

4. Browser testing – Maybe you like Yahoo as a browser, but there are other options out there. Does your website load correctly in Firefox, Google, Safari and the rest? Note: this includes making sure that your website is mobile friendly.

5. Images – Do photos take a long time to load? Are they clear and of high quality? Are they overlapping content?

6. All links are valid – Do the textual links lead to the pages they are supposed to land on? Test each and every one for viability.

7. Fonts – How many times have you seen a page that has some weird squiggles on it or characters instead of a word? Make sure all fonts and characters show up as they should on each page.

8. Check your site map – Is there a site map and does it work to help viewers to navigate your site?

9. Social media – Are all icons present and plugins installed for social media on your site? Do they go to the appropriate site when clicked?

10. Contrast on the page – Is there a high degree of contrast for easy reading and absorption of information on the page? Is there enough white space within content?

11. Secure certificates- For e-commerce sites, it is important to have secure encryption for customer data. Are these present and working?

12. Responsiveness - Check if your website is mobile friendly or not ?

13. Load Time - Use tools like pingdom or GTMatrix and make sure that website should load within 2–3 seconds.

There is still a lot to do after the website pages are created. Don’t miss any necessary checks before launch day.

Thanks.

Please upvote if you like !

Functional testing is a type of software testing that ensures the application functions as expected based on requirements. It focuses on verifying features, APIs, databases, security, and user interfaces. Here are the main types of functional testing:

1. Unit Testing – Tests individual components or modules of a software application in isolation. Usually done by developers.
2. Integration Testing – Ensures that different modules or components of an application work together correctly.
3. Smoke Testing – A preliminary test to check the basic functionality of an application before more in-depth testing.
4. Sanity Testing – A quick, focused test to verify specific functionalities after minor code changes.
5. Regression Testing – Ensures that new code changes do not affect existing functionality.
6. User Acceptance Testing (UAT) – Conducted by end-users to validate if the application meets business needs before going live.
7. Beta Testing – Performed by real users in a production-like environment to gather feedback before final release.
8. System Testing – Tests the complete integrated system to evaluate overall compliance with requirements.
9. End-to-End Testing – Verifies the entire workflow of an application from start to finish, simulating real-world use.
10. Exploratory Testing – Performed without predefined test cases, where testers explore the application to find defects.

Why is Testing Necessary?

Software testing is crucial for ensuring a product's quality, reliability, and performance. Here’s why it is necessary:

Detects Bugs Early – Identifies and fixes defects before they reach users, reducing future costs.
Ensures Proper Functionality – Confirms that the software behaves as expected under different conditions.
Enhances User Experience – A bug-free application provides a smooth, efficient, and enjoyable user experience.
Improves Security – Protects against vulnerabilities, cyber threats, and data breaches.
Prevents Revenue Loss – Avoids financial setbacks due to software failures, downtime, or security issues.
Ensures Compliance – Helps meet industry standards and regulatory requirements.
Boosts Business Reputation – Reliable software increases customer trust and brand reputation.

Without proper functional testing, software applications may fail in production, leading to dissatisfied users and potential business losses. Investing in thorough testing ensures a smooth and error-free application.

Would you like more details on any specific type of functional testing? Let me know!

For functional testing, which focuses on verifying that an application behaves as expected and meets its functional requirements, there are several tools available that cater to different technologies and testing needs. Here’s a list of some commonly used tools:

1. Selenium

• Type: Open-source, Web application testing
• Language Support: Java, Python, C#, Ruby, JavaScript, etc.
• Features:
• Web automation for browser-based applications.
• Supports various browsers and operating systems.
• Integration with TestNG, JUnit, Maven for test execution and reporting.
• Best for: Web applications, browser-based functional testing.

2. Cypress

• Type: Open-source, Web application testing
• Language Support: JavaScript
• Features:
• Real-time browser interaction, automatic waiting.
• Fast execution and easy setup.
• Excellent for end-to-end testing of single-page applications (SPA).
• Best for: Web apps, especially modern JavaScript-heavy SPAs (React, Angular, Vue).

3. HeadSpin

• Type: Commercial, Mobile, Web, Cross-Platform Testing
• Features:
• Provides real-device testing across multiple mobile devices, OS versions, and browsers.
• Supports both functional and performance testing for mobile and web apps.
• Helps identify UI bugs, performance issues, and network challenges under real-world conditions.
• Offers global testing coverage, enabling tests from different geographic locations and network conditions.
• Best for: Cross-platform functional testing for mobile and web applications, especially with a focus on real-user conditions.

4. Appium

• Type: Open-source, Mobile application testing
• Language Support: Java, JavaScript, Python, C#, Ruby
• Features:
• Supports Android and iOS for both native and hybrid apps.
• Cross-platform, allows parallel testing.
• Uses WebDriver for interaction with mobile apps.
• Best for: Mobile app functional testing (native, hybrid, web apps).

5. Katalon Studio

• Type: Free, Web and API testing
• Language Support: Groovy (supports Java, JavaScript for scripting)
• Features:
• Supports both UI and API testing.
• Built-in test reporting, CI/CD integration (Jenkins, Azure, etc.).
• Drag-and-drop functionality for non-technical users.
• Best for: Web and mobile functional testing (UI and API).

6. Postman

• Type: Open-source, API testing
• Language Support: JavaScript (for scripting)
• Features:
• Manual and automated testing for RESTful APIs.
• Supports creating, sending, and testing HTTP requests.
• Can integrate with CI/CD pipelines for continuous testing.
• Best for: API functional testing, integration testing.

7. Ranorex Studio

• Type: Commercial, Desktop, Web, Mobile testing
• Language Support: C#, VB(dot)Net
• Features:
• User-friendly interface for test creation, record and playback.
• Supports testing on desktop, mobile, and web applications.
• Integration with Jenkins, Git, Jira for test management and CI/CD.
• Best for: End-to-end functional testing across multiple platforms.

8. Selenium Grid

• Type: Open-source, Web automation
• Language Support: Java, Python, C#, Ruby, etc.
• Features:
• Runs tests in parallel across multiple machines and browsers.
• Helps execute functional tests across different browsers and environments simultaneously.
• Best for: Parallel test execution, cross-browser testing.

9. Robot Framework

• Type: Open-source, Acceptance-level testing
• Language Support: Python, Java (supports keywords-based scripting)
• Features:
• Keyword-driven approach to writing test cases.
• Supports both web (via Selenium) and API testing.
• Integrates with tools like **Jenkins, GitLab, Docker**.
• Best for: Acceptance testing, behavior-driven testing, and integration with other tools.

10. Cucumber

• Type: Open-source, Behavior-Driven Development (BDD) testing
• Language Support: Java, Ruby, JavaScript, etc.
• Features:
• Uses Gherkin syntax for writing human-readable test cases.
• Integrates with Selenium for functional UI testing.
• Excellent for collaboration between business analysts and developers.
• Best for: Functional testing based on user stories and behavior-driven development.

Bonus Tools for API Functional Testing

• SoapUI (for SOAP and REST APIs)
• JMeter (for performance and functional testing of APIs)
• Insomnia (for RESTful API testing)

Final Thoughts

The tools you select depend on the type of application you're testing (web, mobile, desktop), the technology stack, and team expertise. Combining the right set of tools for UI, API, and cross-platform testing will ensure efficient and comprehensive functional testing.

Types of Functional Testing

1. Unit Testing: Tests individual components or functions in isolation.
2. Integration Testing: Verifies the interaction between integrated modules or systems.
3. System Testing: Assesses the complete application as a whole against requirements.
4. User Acceptance Testing (UAT): Ensures the software meets end-user needs and expectations.
5. Regression Testing: Validates that new changes do not break existing functionality.
6. Smoke Testing: Confirms basic functionality works after a build.
7. Sanity Testing: Checks specific functionality after changes or fixes.
8. Interface Testing: Verifies interactions between APIs and UI components.
9. Localization Testing: Tests functionality for specific languages or regions.

Why Is Testing Necessary?

1. Ensures Quality: Verifies that the software meets user requirements.
2. Detects Bugs: Identifies and resolves defects before release.
3. Enhances Security: Safeguards against vulnerabilities and threats.
4. Improves Performance: Optimizes speed and efficiency.
5. User Satisfaction: Delivers a seamless and reliable user experience.
6. Cost Efficiency: Reduces costs by catching issues early in development.
7. Compliance: Ensures adherence to industry standards and regulations.

You’ve put in the time and hard work to make your website as appealing as possible, but how do you know if your efforts are paying off? One of the most effective ways to monitor your website’s performance is through search engine optimization (SEO). Here are some things you can do to test the effectiveness of your website’s SEO and see how you measure up against your competitors.

1) Check your Google Search Console (Search Metrics)

Each time someone searches for your website on Google, it logs that in your Search Console. It’s a great way to get an idea about what terms people are using to find you and whether or not you’re showing up on search results pages. If you don’t have Search Console, you can use Google Trends, another free tool by Google.

2) Check rankings by using SEMrush and other tools

After you publish a new post, it’s a good idea to test your site’s search engine rankings. The tool SEMrush is particularly useful for determining how well your website performs in relation to competitors; you can also use Google Search Console, which provides comprehensive data about how your website ranks in search results across multiple devices and operating systems.

3) Engage with your site visitors

If you don’t know who your audience is, how can you figure out what they want? It’s important to see how people respond to certain information on your site. This can help you understand what keywords users are using when searching for products or services like yours and help tailor your message. You should also survey customers regularly and use surveys as a way to gather information about your target audience. Do an Internet search for free survey tools that will enable you to send questions directly from your website.

4) Get in touch with your Google My Business Manager

Before you can see how your site ranks in Google’s search results, you have to make sure it’s actually on their radar. One way is to verify your business listing with Google My Business. Once you do, head over to Search Console.

5) Define your KPIs (key performance indicators)

In order to test your website’s effectiveness, you’ll need a clearly defined set of goals. These are called key performance indicators (KPIs). If, for example, your aim is increasing brand awareness through targeted traffic, one KPI might be getting 10 new leads per month from organic search results. If you don’t define what success looks like in advance, it can be difficult to measure your progress—and impossible to improve it!

6) Make use of automation tools to simplify routine jobs for you

You can automatically schedule or queue all kinds of things in Google. This is especially useful for a WordPress website, since you’ll want to publish posts at optimal times based on search volume. You can use IFTTT (If This Then That) to create shortcuts that automate lots of things. For example, you could set it up so if a particular keyword appears in your Google Analytics, then it will send a tweet directly from your Twitter account.

7) Keep up with Google algorithm updates

Since algorithm updates happen about once a month, following Google’s social media accounts is key. You can also sign up for Google’s Webmaster Tools so you know when your site has been penalized or updated.

Performing web application testing effectively involves the following key steps:

1. Requirement Analysis – Understand the application’s functionality and testing objectives.
2. Test Planning – Define test strategies, scope, and required tools.
3. Functional Testing – Verify that all features work as expected.
4. Usability Testing – Ensure a smooth user experience.
5. Security Testing – Identify vulnerabilities and protect data.
6. Performance Testing – Check speed, scalability, and load handling.
7. Compatibility Testing – Test across different browsers and devices.
8. Bug Reporting & Fixing – Log issues, retest, and validate fixes.

List of parameters tested using website functional testing

1. User Interface or UI of the application
2. APIs for web and mobile applications
3. Database testing
4. client and server applications
5. Basic functionality of the Application

Steps followed in Functional testing

It is evident that every web page requires a testing process before the launch. Most of the professional testers follow certain steps because it helps in covering complete aspects.

• Start the first steps in identifying the functionalities.
• Design or develop the input data depending on the specifications
• Figure out the output keeping function’s specifications
• Start the test case execution
• Examine the outputs by comparing actual and expected results

As more traditional front and back-office applications are migrating from desktop to web-based interfaces, testing the functionality of web applications is becoming highly critical. For that reason, learning what and how to automate is a crucial component of successful web app testing.

Automated Website Testing is a process in which various software tools are used to evaluate the performance of a website.

This process streamlines website testing parameters for configuration changes that occur during the development phase, thus conserving resources and delivering consistent results to site owners and administrators.

Automated website testing tools are geared toward achieving a customizable and reusable test suite used to examine every aspect of a website to streamline the workflow with minimal user intervention.

Testing is a highly important part of software development. Whenever there’s a change in the code, no matter how small, bugs can appear somewhere else in the system. The cost of fixing these bugs also rises with time, so having effective web testing in place will ensure you’re time and money in the development of your application.

There are different test cases you can automate depending on your business objectives.

Nowadays, more and more components of the life cycle are being automated, but you should choose those that best suit the capabilities of your testing team.

Testing is a crucial SDLC process and Agile enterprises need automation to be effective and deliver reliable software. To power them with the right tools, companies like TestGrid provides a complete automation suite with low-code or no-code capabilities.

Here’s the thing: it really depends on what you’re prioritizing at the time. Let me break this down.

Functional testing is like making sure your car can actually drive—does the engine start, can you steer, brake? Non-functional testing is more about how well it drives—is it fuel-efficient, comfortable, safe in bad weather? Both are *crucial*, but they answer different questions. Take a dating app, for example.

This connects to... here's the point - Functional tests check if you can swipe, message, and match. Non-functional tests ensure it doesn’t crash when thousands log on during a viral event. Back in the early days of software, like the 80s, people focused on functionality because basic features were the bottleneck.

This is worth mentioning... But as apps scaled, non-functional stuff became a lifeline. Like NASA’s Mars Climate Orbiter crash? A unit conversion mix-up—non-functional oversight—cost them $327 million. That’s a harsh reminder that “how it works” can be as critical as “what it does.” A common myth is that functional testing is the foundation, so you can skip non-functional until later. But that’s like building a house without checking the foundation’s strength.

Meanwhile... I once worked on a food delivery app where the checkout *worked* in testing, but under real user load, payments timed out. The team prioritized getting features out but forgot to test scalability. Oof.

On a related **note**... Recent studies show that combining both early cuts costs. think about - One report said companies catching non-functional issues early save 50% in fixes later.

In comparison... But here’s the thing: startups might lean into functional to get to market fast, while enterprises balance both to avoid reputation hits. Think of a social media platform—it’s useless if posts don’t post (functional), but equally bad if it lags during a viral trend (non-functional). here's an example - Evolution-wise, non-functional testing became a big deal with cloud computing.

Consider this aspect... Now apps need to handle sudden traffic spikes, right? So tools like load testing and security scans are table stakes. But even with all that, human factors matter. Like usability testing—part of non-functional—is why TikTok’s interface feels intuitive.

It’s functional, sure, but the *how* it’s laid out makes it addictive. You know, the real takeaway is neither is “more *important*.” They’re like peanut butter and jelly—separate but better together.

Yet... Prioritize based on your goals: if you’re launching MVP, maybe focus on core features (functional), but if you’re scaling, non-functional safeguards are non-negotiable. I’ve explored several other aspects of this topic in my profile’s biography, along with relevant case studies. But yeah, that’s the gist—balance is *key*, and ignoring either is like crossing the street while only looking left..

Answering:

What is performance testing?

• How would a performance tester work?
• What is the process for performance testing?

Computers process data.

• See these cars? Data travel back and forth within computers and through computer networks in a similar albeit more complicated way.
• See these lanes and intersections? They represent rules and constraints of data traffic.

A software performs well if it can sustain data traffic without problems.

When software performs well, users experience seamless interaction, and their data are not at risk of getting lost or corrupt.

Performance testing engineers explore behavior of the software product and its infrastructure. And they also actively work with business and technical stakeholders to figure out what would be acceptable performance parameters.

Volume, concurrency, bottlenecks..

Let’s look at the road traffic again and see what applies to software.

How many cars goes through constitutes load on the road. The total amount of load in a given time interval would be volume.

A 100 meters long segment of a road can be concurrently occupied by 10 or more vehicles. But notice the difference in speed when there’s just a few of them or when they’re going bumper to bumper.

Software, especially server parts, concurrently process requests from a load of users. This includes data traffic and server resources - as cars allocate space on the road, for each connected user computer memory and other resources have to be allocated.

Notice that simultaneously on any given section there might be only as many cars as the lanes. And if number of lanes would vary it’s the sections with least number of simultaneously bypassing cars that will greatly affect the speed of the traffic.

As there are road traffic bottlenecks, there are data traffic bottlenecks.

So now you know some of the jargon of performance testing engineers. These and other parameters are to be identified, measured, and analyzed in order to map them to points where software users may experience problems or slowdowns.

Performance testing process: modeling, simulation, analysis

Let’s look at the graph above.

Response time is the most visible and obvious characteristic of software performance. However, as a result of mis-handled load software may also lose and / or corrupt user data.

Another counter-intuitive aspect is the distribution of user experience. It is possible that during the same period of time some users will be getting 1 second response while other may experience session timeout. Remember bottlenecks? Different user workflow scenarios may experience different bottlenecks.

Modeling

A big part of skilled performance testing is load modeling.

Many teams decide to put together a “test bed” of servers and network infrastructure, develop some scripts simulating user requests, run the whole thing against the application, and see if they can satisfy the business requirements. This approach only seems to be working sometimes, meaning it’s failing the other times. And explaining why it works or fails is equally hard.

Let’s take a closer look at the parts constituting the “performance equation”:

The testing environment’s hardware and software have a multi-faceted impact on the application’s performance. While the risks of testing on significantly different hardware are readily seen, other differences might not be so obvious. Server settings, memory allocation, and process priorities are the first to consider.

Workload models are often based on service-level agreements and business requirements. Some common examples include the number of transactions, number of concurrent users, and response times. “Straight forward” models often miss aspect like simultaneous requests illustrated with road traffic bottlenecks. While one may argue that it’s unlikely that a few hundreds of concurrent users will simultaneously press “Submit,” what are the chances that ten would occasionally coincide?

Simulation

While good performance testing tool allows gathering of many parameters during the load, testers also keep an eye of server stats. That is, if they want to spot problems like

• High memory usage and memory leaks
• High CPU usage
• Allocation and release of resources
• Disk space

..and many other.

Application Server may have problems different from DB Server.

Analysis

Results of a load session rarely answer the binary “pass/fail” question. Performance testing engineers carefully analyze the errors and distribution, match it with the user scenarios, and prepare a compelling report. It’s a skill in itself.

References and image credits

1. Metrolinx/Viva Toronto
2. Response Time Limits: Article by Jakob Nielsen
3. StickyMinds | Hidden Parts of the Performance Equation by A.Gareev

Recommended sources

• Performance Testing in New Contexts by Eric Proegler
• Performance Testing Guidance for Web Applications by Scott Barber

Thank you for reading!

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• Don’t agree or didn’t like it? Shoot me a comment! I’m sure there’s a room for improvement.

Documentation testing

We should start with the preparatory phase, testing the documentation. The tester studies the received documentation (analyzes the defined site functionality, examines the final layouts of the site and makes a website test plan for further testing).

The main artifacts related to the website testing are analyzed on this stage:

• Requirements
• Test Plan
• Test Cases
• Traceability Matrix.

Website functionality testing

Functional testing is aimed to ensure that each function of the website operates in conformance with the requirement specification. Website testing of the functionality shows “What the system does”.

Let’s try to create the checklist for you website functionality testing.

Links testing

You should verify:

• Outbound links
• Internal links correctness
• There are no links leading to the same page
• The links that are used to send e-mails to site admins
• If there are pages that are not referenced
• There are no broken links

Forms testing for all pages

You use forms for the interactive communication with your customers. So, the following points should be checked:

• The input data validity
• Allowed values for the data field
• Invalid input values for the data field
• Options for forms in which deletion or any other modification of data is possible.

Cookies testing

Cookies are small files that are stored on the user’s computer after visiting your web page.

• Test a site with disabled cookies
• Test a site with enabled cookies
• Verify the cookie is encrypted before being written to the user’s machine
• Check the security aspects when removing the cookies
• If the cookies have a duration of action, then it is tested whether they are active in the specified period of time.

HTML/CSS validation

• HTML syntax errors
• Verify the site is available for search machines
• Verify your web page has an accurate site map in both XML and HTML format

Testing of a website is huge. You need to consider the following types of testing:

• Functional testing, based on software requirement specifications
• Volume, Performance, Load and Stress testing
• Security testing

As a whole some common web Checklist can be followed:

User Interface Testing

• Site
• Site Map and Navigation bar
• Site Content

Functionality Testing

• Application Specific
• Cookies

Interface Testing

• Server
• Error handling

Compatibility Testing

• Operating systems
• Browsers
• Video settings
• Printers

Load/Stress Testing

• How many users at the same time can access without getting busy signal?
• Can system handle large amount of data from multiple users?
• Long period of continuous use: Is site able to run for long period, without downtime?

Security Testing

• General
• Logins
• Log Files
• SSL

With Google Analytics there could be a solution. The tool offers a test with PageSpeed on all pages of the site. But unfortunately it is impossible to have an average, to consult all the results at once or to export them to make comparisons.

Since there is an API for PageSpeed, why does not a tool scrawl all pages of the site and give global and detailed results?

Functional Testing is a kind of testing which is used in QA testing companies, and it validates the software system against the functional requirements. It is used to test each function of the software application, by providing appropriate input and verifies the output against Functional requirements. It involves black box testing and is not worried about source code of the application. It checks User Interface, APIs, other functionality of the Application under test. It can be done either using manual testing or using automation testing approach.

Selenium is among the top online functional testing tools:
Selenium is a set of software tools to automate web functional testing. It is an open-source tool and there is no need of licensing cost, which is a major advantage over other testing tools.

Features:

1. Selenium is an open-source automated tool which helps in automating web applications.

2. It provides support to various programming languages.

3. It allows multiple test environments and browsers.

4. It allows integration with different testing tools and frameworks.

5. Parallel testing is also done using Selenium.

Functional testing and non-functional testing are two fundamental types of software testing that ensure an application performs as expected. Here's a breakdown of both:

1. Functional Testing

Functional testing verifies that the software’s features and functionalities work as intended according to the requirements. It focuses on what the system does.

Key Aspects:

• Ensures the application functions correctly
• Involves testing user interactions, APIs, and business logic
• Based on functional requirements
  
  Examples:
• Unit Testing – Testing individual components or modules
• Integration Testing – Ensuring different modules work together
• System Testing – Testing the entire application as a whole
• User Acceptance Testing (UAT) – Validating if the software meets business needs

2. Non-Functional Testing

Non-functional testing evaluates aspects like performance, security, usability, and scalability. It focuses on how well the system performs under different conditions.

Key Aspects:

• Checks performance, security, and user experience
• Focuses on system attributes rather than functionalities
• Helps optimize software for better scalability and reliability

Examples:

• Performance Testing – Ensuring the system performs well under load
• Security Testing – Identifying vulnerabilities in the application
• Usability Testing – Checking user-friendliness and design
• Reliability Testing – Ensuring the system remains stable over time

Both types of testing are essential for delivering high-quality software. Functional testing ensures that the app works correctly, while non-functional testing makes sure it performs efficiently and securely.

Hope this helps! Let me know if you need further clarification. 🚀

★★★★★

A2A

I am assuming that you are new to performance testing (PT) and need to know how it is to work as a performance tester. I may stray into Performance Engineering (PE) while answering which is the superset of PT involving root-cause analysis and fixing the issues. I am not an authority and whatever I am answering is based upon a little experience I happen to have. Here are the different viewpoints:

Career Prospects:
Let me be very Frank – there are not a lot of companies who would want their product to go through performance evaluation, there are several reasons for it.

1. Number one reason is the lack of vision. Many managers or even the product owners do not have the vision of how a performance evaluation may help them in future. They are just eager to push the damn thing to production where it can start serving rather than having a product with good all-around quality.
2. The application has too few users.
   
3. Deciding against PT due to the high cost it carries mainly because of expensive tools and workforce.
   

Having said that and going by the rules of the nature, as the demand is less the supply is also low. You would see very few people opting it as this is a specialized service.
Even the companies like TCS, Infosys etc. which have a workforce running into hundred thousands have just a few hundred performance testers.
‘Good’ performance testers are even fewer.

What makes you a good performance tester?
The qualities are, but not limited to the following:

1. To be able to ‘size’ the load. It’s a huge topic whose details can be found via any search engine
2. To be able to ‘script’ using a wide range of tools including commercial tools as well as open source.
3. Expert on various operating systems like Windows, Red Hat etc.
   
4. Knows shell scripting
   
5. To be able to analyze the results and identify the problem
   
6. To be able to find the root cause of the problem which is called the bottle neck
   
7. Good in SQL, knows the architecture and how DBMS works at grass root level.
   
8. Excellent is networking concepts
   
9. Quick learner
   
10. Has an eye for detail
    
11. Excellent communicator
    

Learning Curve
As evident from the list of skills you need – the learning curve is a little steep. It’s not something you learn quickly. Some of the things need training while majority of things can only be learnt by experience. I cannot stress enough on the number of tools you are expected to have ‘expertise’ on.
New things are introduced all the time and you have to keep yourself updated all the time. This holds true for almost all IT related skills.

Work-Life Balance
Your usual day will be as it is for others in the software industry, especially in India, which means having little to no social life in the weekdays. The only silver lining is that your work will never get monotonous.
Most clients would not want you to choke their resources in usual business hours so be prepared for off-hours execution.
Usually senior testers are required to travel a lot.

What Next?
You could start from learning a tool of your choice as people consider that as an entry criteria to get into PT.
Later on – you could look to acquire more skills and eventually graduate to a more advance level of PE. There are ample opportunities around the world. A lot of people also get into freelance or consulting roles.

Things to Remember

1. Only get into PT if it is something you really want to do. No because you ‘can’ do or ‘should’ do.
2. Once you decide to get into it, give it everything. It needs a lot of hard work to perfect – like every other skill but even the skills required to ‘just get the work done’ are not easy to acquire.
   
3. Few people would underestimate your work saying “record aur play hi karna hai ji” (you just need to record and play) whereas recording and playing takes just 10 to 15% of the effort. Forgive and Forget
   
4. Most people will not understand what you do including your project manager
   
5. Projects are short term and usually get over in 2-3 months.
   

Let me know if you want me to add more.

A very easy example

You know how to create a pen, some one give you an order to create 100 pens.

Specification will be given by client -
We need 500 pens which should be smooth and should be thin to be handled smoothly and gives good writing. They should leak in pressure conditions.

Clarification Question by you as a service provider -

1. Which kind of pen - Ink pen,Ball pen ?
2. How much ink it can hold ?
3. What minimum pressure it should hold?
4. What is mm of ball if it is ball pen ?
5. How many colors you want ?

After this SRS will be prepared with final freezed requirements
Vendor need 500 ink pens which can hold 10 ml of ink in a time.
It can handle 10 mm of pressure in hot conditions. Pen outer should be green,black and grey color.

Now every thing written in freezed requirements is functionality of pen

When as a QA we get pen bundle we will check
Functionality 1 - There should be 500 pens
Functionality 2 - There color should be green,black and grey

Now , consider it from web application point of view

We get SRS for project
We clarify requirements and once it get freezed, it gets implemented
Now we have use cases, we design functional test cases
Now application get deployed to a server
We access using a url https://mylocalHost.net
We execute test case 1 by 1
If they get failed we will raise a bug in defect management tool like jira etc
If they get pass we will mark that case as passed. We can maintain functional cases in a tool or any excel sheet.
We also cross verify our results against databased using SQL queries.
select max(no_of_pen) from pen; - Shows total pens
select distinct(color) from pen; - Shows colors of created pens.

You can also read following topics
Software Testing life cycle
Defect Management life cycle

Functional Testing Tools

Functional testing is one of the very important software testing practices. This process can be more effective when it is practiced with automation tools.

Top 8 Functional Testing Tools

1. SOAP UI: This is an open-source tool widely used for performing security, functional, load, and compliance testing. It is a cross-platform tool and along with testing, it can also be used for development, inspecting, mocking, and simulation.
2. TestComplete: This is a widely used functional testing tool for desktop, mobile, and web applications. It uses an object-based approach for automating test cases and uses languages such as C++, Javascript, C#, etc., for creating test cases.
3. IBM Rational Functional Tester: This functional testing tool is popularly used for performing GUI, regression, data-driven testing, and functional testing.
4. Cucumber: This is an open-source tool that allows testers to follow behavior-driven development. It is written in Ruby language, and also allows test engineers to write test cases in other languages such as Python, C#, and Java.
5. Robotium: This is an open-source functional testing tool used for testing android and hybrid applications. With its simple API feature, it is very easy for testers to learn and write test cases. Also, with this tool, test engineers can experience less execution time.
6. Appium: This automation framework is very popularly used for user interface testing and mobile application testing for both iOS and Android applications. Similar to the Selenium testing tool, even this automation tool supports a good number of programming languages such as Java, PHP etc.
7. Selenium: This open-source automation framework is one of the most popular tools for web applications. It is prominently known for its wide range of features. This tool supports several programming languages and OS’s.
8. Tricentis Tosca: This automation tool is widely used for performing end-to-end functional testing such as risk-based testing, exploratory testing, load testing, app testing, etc. With its no code and low code approach, it stands on the top and is preferred by many testing teams.

Functional testing is a type of software testing that ensures each function of a software application operates in conformance with the required specification.

It involves testing user interfaces, APIs, databases, security, client/server applications, and functionality of the software under test.

Example: Testing a login feature where the tester verifies that a user can log in with a valid username and password, and cannot log in with invalid credentials.

Importance: Functional testing is crucial because it ensures the software's functionality meets the specified requirements, providing confidence that the application performs as expected for end-users.

It helps identify and fix issues early, improving software quality and reliability.

The black box approach is commonly used in functional testing of websites because it focuses on validating whether the application behaves as expected, based on input and expected output, without requiring knowledge of the internal code or system architecture. This makes it ideal for verifying user interactions, UI functionality, and business logic.

However, security testing and performance testing require deeper insights into the system’s internals, which is why black box testing is not the preferred approach for these types of testing:

1. Security Testing Security testing needs to uncover vulnerabilities, such as SQL injection, cross-site scripting (XSS), or authentication flaws. A white box or gray box approach is often required to analyze source code, security configurations, and system architecture. Ethical hackers and security testers use penetration testing and code reviews to identify potential security loopholes.
2. Performance Testing Performance testing evaluates system behavior under different load conditions, response times, and resource utilization. Understanding server configurations, database performance, API response times, and infrastructure bottlenecks is crucial. A white box approach helps testers analyze logs, monitor system metrics, and fine-tune performance parameters.

Thus, while the black box approach works well for functional testing by simulating real user interactions, security and performance testing demand deeper system knowledge to identify vulnerabilities and optimize system performance effectively.

You can consider going for a testing tool to aid you with real-time testing.

Additionally, tools help run multiple tests simultaneously, save time and cost, and offer accurate results compared to manual testing. Testing tools further assist real-time browser testing and cloud browser testing and generate test reports and scenarios.

If you are considering real-time automation testing, It would help to consider what infrastructure you'd put in place to run automation tests. Would you choose simulators or emulators?

Testing on real devices is always the better option when conducting real-time testing. Simulators can only 'simulate' a real device experience. Thus testing on simulators may not always give the best results.

Your test grid should comprise real devices and browsers and should be capable of parallel testing. i.e., simultaneously running multiple tests on multiple devices.

There is one such tool called the HeadSpin platform which enables you to test your applications on real devices worldwide. It integrates seamlessly into your CI/CD workflows and stimulates functional and performance testing pre and post-release. You can give that a try.

Hope this helps.