What is Automation Testing? A Practical Guide

Automation testing is now the default for modern QA teams. Instead of spending hours manually clicking buttons, filling out forms, and triple-checking for bugs (only to miss one in production), testers can write a script once, and the machine takes over. It can mimic the user’s actions, flags issues, and gives teams back hours that they can use for more strategic tasks.

When done right, automation testing is a game-changer.

In this article, we'll cover everything you need to know about automation testing, when to do automation testing, what to automate, the automation testing process, and the tools to do it properly.

What is automation testing?

Automation testing is the practice of using scripts and specialized tools to automate the execution of tests to check for issues in the system and ensure that it is working as expected.

When you run an automation script, it basically tells the app exactly what to do, just like a tester would, but without needing a human to manually click through every step.

[I see] automation testing as an addition to testing basically, because automation testing or test automation or automated scripts help us to free up the time of a software tester.

Daniel Knott

QA Leader & Influencer

Automation testing vs. manual testing: Key differences

Simply put:

• Manual testing involves a human tester manually interacting with the system to find bugs.
• Automation testing involves writing a script to command the system to perform test steps for humans.

Here's a simple comparison table for you to get an idea of the key differences between manual testing and automation testing:

Want to see an example of manual testing? Let's Game It Out is the best example for this. The man behind this YouTube channel plays games in the most boundary-breaking ways possible. In this video, he's using one single item to completely break the game.

On the surface, it looks like he is just messing around, but boundary-pushing is exactly what a manual tester does on a daily basis.

Once a bug is discovered, testers can then leverage automation testing frameworks or automation testing tools to help them automate the tests to check for bugs that they previously found manually.

Benefits of automation testing

Automation testing is the best way to enhance effectiveness, broaden test coverage, and improve execution speed. Here are some of the obvious benefits you can get from automation testing:

1. Automation testing dramatically boosts accuracy: manual testers can misclick, skip a step, or misinterpret results, especially after repeating the same flow for the 100th time. Automation doesn’t get tired, bored, or distracted. If the test is well-written, it runs the exact same way every single time.
2. Test automation gives you speed you simply can’t match manually: automated tests run in parallel across browsers, APIs, or data sets. That means you can turn a 2-day manual regression cycle into an hour-long pipeline job.
3. Automated testing removes inconsistency from the QA process: different testers interpret things differently. Automation removes the human factor where it doesn’t belong so that manual effort is saved for things that actually require judgment (like UX quirks, accessibility, or exploratory logic).
4. It saves money: test automation is front-loaded work. The payoff comes when you stop repeating the same tests every sprint. Over time, it reduces hours of manual labor and lets QA engineers focus on high-impact edge cases, not “does the login button still work?”
5. Automation scales testing faster than your team ever could: when your app grows from 20 to 200 features and across 5 environments, manual testing simply can’t keep up. Automation lets you grow coverage without scaling headcount linearly.
6. Automation testing frees humans to do what automation can’t: there’s nothing creative about clicking “next” 50 times. Automation handles the boring stuff so testers can spend their energy on exploratory work, scenario design, and finding bugs that no script could anticipate.
   
   

📚 Read More: Benefits of Automation Testing You Should Know

Challenges of automation testing

Of course, automation testing is not without its challenges. There is usually some compromise to be made when you want to increase testing speed. What’s important is whether that compromise is worth it or not. 

According to the State of Quality Report 2024, the most prevalent challenge to automation testing is the team's lack of skills and experience in test automation, with up to 45% of respondents agreeing, followed by 38% thinking that requirements change too often, and another 26% claiming that test maintenance is costly.

Which test cases to automate?

Yes, automation testing is awesome, but not all tests can be automated. It’s all about “automation feasibility”.

So, what makes a test case feasible for automation? There are several:

1. Tests that need to be run frequently and repeatedly
2. Tests that require large datasets and many iterations
3. Tests that take too long or just tedious when done manually
4. Tests requiring execution on multiple hardware and software platforms
   

Before starting automation testing, make sure to go through this step. Striking a nice balance between manual tests for ad-hoc, non-repetitive test cases and automated tests for time-consuming, repetitive test cases is how you maximize test coverage.

💡 Read More: How to select test cases for automation? A guide on the test case selection matrix

Types of automation testing

Note that automation testing is only an approach to testing. What it means is that virtually any type of tests can be done automatically. You only need to write scripts for it. However, certain types of tests are more suitable to be automated than others.

Here are the types of tests that should be automated:

• Automated Smoke Tests: These are basic checks to ensure core functionality works. Since they are fast, simple, and highly repetitive, automation is totally worth it.
• Automated Regression Tests: Regression tests, by definition, are tests that are run whenever the code is updated to check if the new code break existing features. The sheer volume and repetitiveness of these tests make manual testing them highly counterproductive. Automated regression testing is the optimal choice for many QA teams.
• Automated Data-Driven Tests: Data-driven testing is essentially running the same test with different data sets. The same rule applies: if it is repetitive, it should be automated.
• Automated Unit Tests: Unit tests are little tests to check individual components or functions in an application. They account for the majority of tests to be executed, so automating them is a good choice.
• Automated Cross-Browser Tests: cross-browser testing ensures that the app works across different browsers and devices. There are approximately 60K+ possible browser-device-OS combinations, so automating cross-browser testing makes a lot of sense.

The process of automation testing

Step 1. Choose your approach

To do automation testing, you have 2 approaches:

1. Use an automation testing framework: A framework gives you the structure, rules, and reusable components for writing and organizing automated tests. It’s the “blueprint” for how your tests are built, executed, and maintained. Examples include Selenium, Cypress, or JUnit frameworks.
2. Use an automation testing tool: A tool is the actual software you run to create, execute, and manage automated tests. It handles the interaction with your application, collects results, and often integrates with CI/CD pipelines. Examples include Katalon, TestComplete, or Playwright.

Here are the pros and cons of each approach:

• Test automation framework: To best utilize a test automation framework, you must have extensive coding knowledge yourself, and the effort to maintain test scripts is significant, but you can freely customize the framework to fit your specific testing needs
• Test automation tool: A testing tool usually comes with out-of-the-box features to help you easily create automated tests much faster. You can switch to coding mode whenever you want (if the tool offers coding mode).

Step 2. Choose test cases to automate

Let’s get one thing straight: Automation ≠ testing everything.

The goal of automation isn’t coverage for the sake of coverage. It’s about speed, stability, and return on effort. Every test you automate should save time, reduce risk, or catch bugs faster than a manual alternative. If it doesn’t, you’re wasting cycles.

If you’re going to automate, automate with intent. Focus on test cases that are:

• High-frequency: Think regression, smoke, and sanity tests. If you run it every sprint or every pull request, it’s a strong candidate.

• Stable and predictable: Avoid automating things that change constantly or behave inconsistently.

• Business-critical: Core flows like login, checkout, or API contract. They are things you must know are working before release.

• Data-driven: Tests where you can reuse logic across many input sets without rewriting.

• Time-consuming to do manually: Tedious flows that eat up hours each release cycle? Perfect for automation.

Automation works best when it's consistent, reliable, and part of your delivery rhythm. On the other hand, here are the kinds of tests you should keep manual, for now or forever:

• One-time or rarely run tests

• Exploratory and UX-focused tests

• Highly unstable features or UI elements

• Tests requiring physical devices or complex hardware

These are the genuinely fun parts of testing. Why automate the fun and creative part? After all, automation is basically using the power of machines to leave more space for us humans to do creative work. Let's all let the machines do their work, while we take care of ours.

Step 3.  Create automation tests

Here's a brief example of an automation test case in Selenium:

from selenium import webdriver
from selenium.webdriver.common.by import By
from selenium.webdriver.common.keys import Keys
import time

# Initialize the Chrome driver
driver = webdriver.Chrome()

try:
    # Open the login page
    driver.get("https://example.com/login")
    
    # Find username and password fields and enter credentials
    username_field = driver.find_element(By.ID, "username")
    password_field = driver.find_element(By.ID, "password")
    
    username_field.send_keys("my_username")
    password_field.send_keys("my_password")
    
    # Submit the form
    login_button = driver.find_element(By.ID, "login-button")
    login_button.click()
    
    # Optional: Wait for page to load
    time.sleep(3)
    
    # Verify login success (simple example: check URL or page text)
    if "dashboard" in driver.current_url.lower():
        print("Login successful!")
    else:
        print("Login failed or incorrect credentials.")

finally:
    # Close the browser
    driver.quit()

This code:

• Opens a login page.
• Fills in username and password fields.
• Clicks the login button.
• Waits briefly, then checks if the dashboard loaded.
• Closes the browser at the end.

Yes. Automation testing requires some coding knowledge. However, if you and your team don't really want to code, you can take a look at some low-code automation testing tools to help you get started quickly.

Step 4. Prepare test environment

There will be clear hardware-software specifications for any testing projects, and that includes requirements on servers, databases, OS, browsers, and any third-party tools needed to perform the test.

For example, if you want to test a Login page, you need to prepare:

• The browsers (Chrome, Safari, Edge)
• Devices in a wide variety of versions (desktop, tablet, laptop, mobile)
• Operating system with suitable versions
• Suitable network conditions

There are 3 types of environment you can go with:

1. Run tests locally with your device being the environment itself
2. Run tests remotely leveraging services like Selenium Grid or virtual machines
3. Run tests on-cloud leveraging platforms like AWS DeviceFarm

Step 5. Execute tests & analyze results

With all test cases ready, you can start test execution and gather results.

📚 Read More: Steps To Build A Good Automation Test Report

Automation testing best practices

How to balance manual testing with automation testing?

There is no doubt that all QA teams want to speed up testing and improve efficiency with automation testing. However, this must be done strategically.

Let's meet @Cristiano Caetano, founder of Zephyr Scale, a top-selling automation test management solution on Atlassian, who is going to share his thoughts on how to balance manual with automation testing:

Most Popular Automation Testing Tools

Automation testing tools are tools that provide ready-to-use platforms for building, executing, managing, and reporting automated tests. Many of them bundle frameworks under the hood and offer added functionality like no-code editors, AI, dashboards, and integrations. Here are some good tools for you to choose from.

• Katalon Studio: all-in-one tool supporting web, mobile, API, desktop testing with no-code to full-code scripting, data-driven testing, AI-powered regression (TrueTest), CI/CD integration, and rich reporting. Testers can always download the Free version, then upgrade to more advanced versions later.

• Katalon TestCloud: another tool that goes with Katalon Studio which allows you to perform cross-browser testing across a wide range of browser & mobile environments
• Katalon TestOps: the test management counterpart of Katalon Studio and Katalon TestCloud, which allows QA teams to do everything test management-related, from planning, scheduling, management, to reporting.

• TestComplete: commercial testing tool for web, mobile, and desktop apps. Offers record & playback, scripting, object recognition, and visual test validation.

• Ranorex Studio: a Windows-based GUI automation tool for web, mobile, and desktop apps with VB.Net/C# support, low-code scripting, and robust UI recognition.

Most Popular Automation Testing Frameworks

Unlike automation testing tools, automation testing frameworks are code-based libraries or toolkits used to build and structure test cases. They often require developer/test engineer setup and provide the flexibility to customize test logic and execution.

• Selenium: The most widely used web automation framework; supports multiple languages and browser automation via WebDriver.

• Appium: Cross-platform mobile testing framework for Android and iOS; uses Selenium WebDriver protocol and supports native, web, and hybrid apps.

• Cypress: Fast and developer-friendly JavaScript framework for end-to-end web testing, operating directly in the browser runtime.

• Playwright: Microsoft-backed framework for modern cross-browser testing (Chromium, Firefox, WebKit) with strong parallelization support.

• Puppeteer: Headless Chrome Node.js API used for automating browser tasks and functional tests, particularly in CI environments. 

How To Choose an Automation Testing Tool/Framework?

Here is a list of top 10 criteria you should consider when choosing an automation testing tool:

1. Is the tool easy to use with a user-friendly interface and a low learning curve?
2. Does it support a wide range of testing types (web, mobile, and API applications)?
3. Does it offer multiple testing modes (no-code, low-code, full-code)?
4. Can it integrate seamlessly with CI/CD pipelines, version control systems, and project management tools?
5. Does it allow easy updates to test scripts when the application changes?
6. Can tests run across multiple environments (browsers, devices, and operating systems)?
7. Does it provide clear, actionable reports?
8. Is the tool suitable for projects of all sizes and capable of growing with your needs?
9. Does it have a strong community, detailed documentation, and reliable technical support?
10. Is the tool feature-rich and within your budget?

Wrapping Up

In conclusion, automation testing is a critical component of any software development process. With the right tools and approach, organizations can improve the speed and accuracy of their testing, catch bugs earlier in the development cycle, and ultimately deliver better products to their customers.
 

If you don't know which test cases to start with, here’s a list of popular test cases for you. They should give you a good foundation of how to approach a system as a tester. 

1. Test Cases For API Testing
2. Test Cases For Login Page
3. Test Cases For Registration Page
4. Test Cases For Banking Application
5. Test Cases For E-commerce website
6. Test Cases For Search Functionality