End-To-End Testing: 2025 Guide for E2E Testing

Modern applications increasingly rely on different interconnected systems. Without proper E2E testing, a single failure in this chain can cause catastrophic downtime, lost revenue, and dissatisfied customers.

This becomes clear when examining industry insights and research findings. Research from the University of Illinois found at least 20% of severe failures in cloud applications stem from cross-system interaction failures and bugs. The prevalence is even higher for open-source applications, with 37% of reported issues attributed to such failures.

Given that major cloud providers like Google and Amazon typically report only the most critical incidents, the catastrophic consequences of these failures cannot be overstated.

End-to-end testing is also crucial for the user experience. By simulating and validating key user journeys, organizations can identify and mitigate potential issues before they escalate, ensuring a seamless and satisfying experience for all users.

In this guide, we explain why E2E testing is essential for maintaining the integrity of your systems and discuss best practices for thorough and efficient testing. We also share real-world examples to illustrate the impact of E2E testing and give some practical implementation tips.

Table of Contents

1. Foundations for E2E Testing

2. Trends and  the why of E2E Testing

3. Examples and cases

4. Benefits and challenges

5. Best practices and automation in E2E

E2E Testing Best Practices
How to Implement E2E Testing in 6 Steps
Manual vs. automated E2E Testing
Choosing Your Governance Model

6. Tools: Our Top Picks & How to Choose

How to choose E2E Testing Tools
Best E2E Testing Tools: Top 7 list

7. Final Remarks & Conclusion

Considerations
Conclusion

What is E2E testing?

End-to-end testing validates whether all system components can run under real-world scenarios by simulating a user’s actions from start to finish.

Imagine a car assembly line where each part is added step-by-step. E2E testing is like running a quality check from the start of the assembly line to the finished car, ensuring every part and process works perfectly together.

It’s not enough for individual features like the wheels, steering wheel, gearbox, and brakes to work independently. They must all function well together.

It doesn't matter if the wheels are perfectly designed, if they don't turn properly when the steering wheel is used, or if the gearbox works in isolation but fails to coordinate with the engine and brakes, then the entire system will fail. E2E testing would ensure that all these components interact correctly, resulting in a car that drives smoothly and safely.

The modern definition of E2E testing is much broader than it used to be. While it used to just look inside a single application, it now typically spans many different applications as E2E business processes operate across different systems.

As businesses become more digitized and complex, the need to ensure that integrated components work flawlessly across applications.

This means validating the system’s integration and data integrity across all interconnected modules, ensuring the entire process functions as intended.

What are E2E testing tools?

E2E testing tools validate whether all system components can function under real-world scenarios by simulating user actions from start to finish.

They ensure that integrated components work together seamlessly, maintaining the overall functionality and performance of the application.

E2E testing tools are essential for catching any bugs that might occur due to broken interactions between different subsystems, providing comprehensive test coverage.

Why E2E testing is important

E2E testing is critical as it assesses your system’s entire workflow, identifying issues that unit or integration tests might miss.

This aligns with the principles of the testing pyramid, a concept that remains a trusted guide in agile software development.

The testing pyramid emphasizes a strong foundation of unit tests, a solid middle layer of integration tests, and a crucial top layer of E2E tests.

End-to-end testing offers a unique and comprehensive view of system behavior that other testing methods can't fully provide, focusing on validating the entire user journey.

Of course, it is important that individual components work as intended. But these components work in tandem and are not siloed, which is why your business should be more concerned about its customer or business user journeys across components and being able to validate these.

You might have a cutting-edge web-based application at the beginning of a process that works perfectly when isolated, but this application might be integrated with multiple legacy applications, and these processes need to be tested.

By validating the complete user journey, businesses can ensure that all parts of the system work together harmoniously, which is essential for maintaining user satisfaction and operational efficiency.

Emerging Trends in End-to-end-testing

End-to-end testing is a trend itself as businesses shift from single app testing to end-to-end testing of entire business user journeys. And these are the trends we see emerging within E2E testing.

1. AI-Enhanced Test Automation

   Concepts like hyperautomation and agentic AI are trending with a potential for huge business value, including automating and delegating manual and labor-intense work such as software testing to AI-Powered platforms. Specific examples of AI-Powered test automation tasks include data-validation, generation of test scenarios and test data, data format transformations, and extracting test insights.

2. Composable Platform Architecture

   Modern platforms allow organizations to build modular and flexible applications by integrating best-in-class software and services tailored to their specific needs. With a composable architecture, the modularity enhances agility and scalability in complex testing environments. This increases the demand for test automation platforms working across technologies and platforms.

3. Cloud Accessibility

   Cloud-based platforms enable centralized test management and execution, allowing distributed teams to collaborate seamlessly. These platforms eliminate the need for heavy on-premises infrastructure, reducing costs and ensuring scalability for dynamic testing demands.

4. Low-Code/No-Code Test Automation

   The rise of low-code and no-code platforms is democratizing E2E testing, allowing non-technical business users to contribute and participate in test automation. Key benefits include faster test creation with drag-and-drop interfaces, and pre-built templates simplify the creation of test workflows.

Why automate end-to-end testing?

Given how broad end-to-end testing is, doing it manually is slow and prone to mistakes, especially when you need to move fast and keep improving your app. Automating these tests means they can run quickly and accurately, spotting issues before they affect users.

As with regression testing, performing the same end-to-end tests again and again manually is extremely time-consuming. It’s also tedious and error prone. There are a multitude of other things you and your team could be doing instead.

For teams following a CI/CD, continuous testing or agile framework, working at speed is crucial to delivery. The only way teams can work faster is by automating time-consuming tests like end-to-end tests.

The consequence of not automating end-to-end testing? A business won’t be notified instantaneously if its system crashes.

Most modern software systems are complex webs of subsystems, and a bug in any of these subsystems can cause the whole system to crash, impacting not just the customer experience, but revenue and trust.

End-to-end testing can help mitigate that risk, and automated end-to-end testing can ensure that software teams have a chance of fixing the issue before the users experience it.

E2E testing example: retail

Consider a retail company with a popular online store. The retailer wants to ensure that every step of the customer journey, from browsing to receiving the product, works seamlessly. E2E testing would involve validating each step of this process.

Here’s a detailed look at the process and the steps that need to be validated:

• Order placement: When a customer places an order through the online store, the system validates the order, checking availability and ensuring real-time inventory data is accurate.  
  Examples: eCommerce, CRM, ERP 
• Payment processing: The system processes the payment through a secure gateway, verifying that all transactions are seamless and secure. 
  Examples: CRM, ERP, Billing, Payment GW 
• Inventory update: Upon payment confirmation, the inventory system updates stock levels, ensuring no overselling or stock discrepancies.
  Example: ERP 
• Order confirmation: The customer receives an order confirmation email with details and an estimated delivery date. This step tests the email integration system for timely and error-free communication.
  Examples: CRM, ERP 
• Shipping logistics: The order details are sent to the warehouse for fulfillment. The warehouse system generates a picking list, ensuring the order information is accurately transmitted and processed.  
  Examples: ERP, Logistics 
• Shipping and delivery: The shipping system calculates the best delivery route and dispatches the order. This step includes verifying that shipping details are updated, and that the customer receives a tracking number to monitor the order until delivery. 
  Examples: ERP, Logistics, Shipment fulfilment.
• Returns management: If the customer needs to return the product, the returns process should be seamless. This step involves validating the returns request submission, updating inventory levels upon receiving the returned product, processing the refund, and sending confirmation emails to the customer.  
  Examples: ERP, CRM, Logistics, Shipment fulfilment. 

It is obvious with this one example just how interconnected these systems can be, and why it is so important to validate each step in this process from start to finish. E2E testing ensures that the entire workflow operates smoothly, maintaining high standards of customer satisfaction. 

Real world E2E testing example: Mattress Firm

Challenge: Mattress Firm aimed to enhance its customer experiences and ensure the seamless operation of Microsoft Dynamics 365, a suite of applications essential for running critical business processes. Any disruption to Dynamics 365 could directly impact customer satisfaction and revenue.

Solution: Mattress Firm sought a robust solution for end-to-end testing from point of sale to delivery. They selected Leapwork for its user-friendly visual automation platform, integration compatibility, and rapid implementation.

Impact: Through Leapwork, Mattress Firm achieved efficient end-to-end testing across core business applications, accelerating development and improving the customer journey. Notably, checkout times were reduced by 20%, significantly improving the point-of-sale experience.

Read Mattress Firm’s story in full

Benefits of E2E testing

Verifying the journey from an end user’s perspective enables you to ensure better quality from a business perspective, not just from an isolated software perspective.

Here are the main benefits:

1. Holistic validation of the entire business process: Ensures the value-adding and revenue-driving business process work together, not just individual components.
2. Improved quality: Detects integration issues, ensuring better data integrity and functional correctness across modules.
3. Enhanced user experience: Validates workflows from the user’s perspective, ensuring smooth and efficient operations.
4. Reduced risk: Identifies and mitigates potential points of failure in the system’s workflow.
5. Business alignment: Ensures IT deliverables align with business requirements, supporting business processes effectively.

Challenges of E2E testing

More complexity can mean more challenges, but also more rewards. 

When testing E2E, you need to collaborate with multiple business teams and units. A cross-team group might include testers, QA managers, application managers, business process owners, and end users. 

This shift to bringing in more stakeholders requires a new mindset.

Here are the main challenges:

1. Complexity: Involves testing across multiple systems and integrations, which can be complex and time-consuming.
2. Resource intensive: Requires significant resources, including time, personnel, and tools, to execute comprehensive E2E tests.
3. Coordination: Necessitates collaboration between various teams and business units, which can be challenging to manage. Process owners are typically quite senior within an organization and have busy calendars. However, as this is a high stakes strategic initiative, it shouldn’t be too difficult to get their interest and involvement, as long as the project is briefed accurately.
4. Maintenance: Keeping E2E tests up to date with system changes can be demanding, requiring continuous effort to maintain test accuracy. 
5. Tooling: Selecting the right tools that can handle diverse applications and technologies involved in the business processes, and reduce the pains above.

E2E testing best practices

Implementing E2E testing requires more than just technical teams. QA should work closely with stakeholders that own applications or processes to become familiar with entire user journeys. Only then can they be properly validated.

Here are some best practices to make your E2E testing more effective. 

Here are some best practices:

1. Early involvement of QA: Bring QA teams into the development process early. They should understand the business processes and requirements from the beginning. This early involvement ensures that QA can plan and design tests that truly reflect the business needs.
2. Metrics for Success: To ensure business value of your E2E test automation, outline the KPI’s to measure effectiveness such as defect detection rate, mean time to resolve, test coverage, deployment/launch frequency etc.
3. Foster collaboration: You need strong collaboration between developers, QA, and business users. QA teams understand the testing mindset, but business users and process owners have deep insights into how processes should work. Working together ensures a better understanding of the entire workflow and more comprehensive test coverage.
4. Use realistic data: You should use realistic test data that mirrors production data as closely as possible. This enhances the accuracy of your tests and ensures that your testing scenarios are relevant. AI is changing the way teams approach test data generation as it can be used to generate synthetic data. 
5. Automation where possible: Automate as much of the E2E testing process as possible. Automation reduces human error, increases efficiency, and allows you to run tests more frequently. However, understand that not everything can or should be automated and you need a test automation strategy. Maintain your risk-based approach automating high-impact, low-complexity test cases first.
6. Regular maintenance: Continuously update and maintain your E2E tests to reflect any changes in the system or business processes. This ensures that your tests remain relevant and accurate over time. Regular maintenance also involves validating that the automated tests still work as expected after updates.

How to implement E2E testing in 6 steps

While E2E testing can be complex, breaking it down into manageable steps can streamline the process and enhance its effectiveness. Here are six key steps to successfully implement E2E testing in your organization:

1. Identify key user journeys: Begin by identifying the key business processes and user flows that need to be tested. Focus on journeys that are critical to your business operations. Examples include order-to-cash and procure-to-pay processes.
2. Design your test cases: Create detailed test cases for each identified scenario. These test cases should cover all possible user interactions and system integrations. Collaborate with business analysts and process owners to ensure all aspects are covered.
3. Set up the test environment: Ensure your test environment closely replicates your production environment. This includes having the same configurations, data, and integrations. A realistic test environment helps in identifying issues that could occur in the live system and actual user journeys.
4. Automate testing: Use an automation platform to build, stabilize, maintain, and scale your E2E testing. Choose a solution that can handle the complexity of your business processes and integrate well with your existing systems.
5. Execute and monitor: Run your tests, monitor the results, and log any issues ensuring broken automation is resolved. Monitoring is crucial in understanding how well your tests are performing and to identify any areas that need improvement.
6. Review and refine: Regularly revisiting your test cases helps in maintaining their relevance and accuracy. Based on feedback and system changes, update your tests to ensure they remain effective. When a new capability is introduced, it’s critical to execute E2E tests alongside other functional tests before pushing updates into production. This approach takes a holistic view, ensuring that any new functionality integrates seamlessly into the entire process, identifying dependencies and potential ripple effects.

Manual vs. automated E2E testing

Manual E2E testing involves human testers executing test cases without automation tools.

Manual testing can be beneficial for complex scenarios that require human judgment and for tests that are run infrequently. However, manual testing can be time-consuming, prone to human error, and less efficient for large-scale testing.

Related reading: What is the Difference Between Manual Testing and Automation Testing?

Automated E2E testing uses software tools to automatically execute test cases and validate the outcomes. This approach is ideal for repetitive and frequent tests, offering higher efficiency, accuracy, and coverage.  

Test automation tools can simulate user interactions across multiple systems, ensuring that all components work together seamlessly.  

Implementing automated E2E testing requires careful planning and the right tools to ensure comprehensive coverage and smooth operation across all integrated systems.  

Popular tools for automated E2E testing include Selenium, Leapwork, and Tricentis Tosca. Automated E2E testing tools can vary significantly in their features, ease of use, and suitability for different types of applications. When selecting your tool, consider the complexity of the workflows you need to automate, the tool’s maintainability, ramp-up time, and your team's skill set. 

Related topic: The Best E2E Testing Tools

Choosing your governance model

Before choosing a governance model, consider evaluating how your test operations and team structure fit the platform integrations and user journey: Is testing managed inside teams today? If so, how easily are they coping with cross-system issues?  

If your organization is looking to bring in automation best practices, it works best with a governance model with centralized test automation experts, also known as a center of excellence.

These experts ensure that team members are trained in automation and act as a center of excellence, providing best practices and guidance. However, the actual contributors to the automation may be key users or business analysts spread across various departments.  

This approach ensures that the expertise is centralized, but the execution is distributed, leveraging the specific knowledge and context of different business units. 

This model can be particularly effective in large organizations where different teams need to collaborate and maintain consistent testing standards across diverse applications and technologies.

How to choose E2E testing tools: main criteria 

To achieve true E2E testing, you need tools that can drive in data and multiple data records into the flow. Additionally, the tools must support various applications, so you need a solution with a very broad technology fit from an automation perspective. 

Selecting a single tool that can handle all applications in one, rather than multiple tools for each application, simplifies the testing process and makes it easier to manage and maintain. 

Choosing the right E2E testing tool involves considering these criteria: 

• Cross-technology capabilities: First of all, you need assurance that the tool you're looking at can work with your application or with your set of applications that constitute the E2E process. The tool should support application types such as web, desktop, mainframe, mobile, and virtual.
• Ease of use and scalability: The tool should be user-friendly, especially for testers who may not be technical users. You want testers to be able to quickly understand and manage the flow. When users can create and maintain tests without having to for example, involve developers, it makes automation more scalable, and in the long term, a much better investment. No code tools and platforms can strengthen the collaboration between QA and the business, as processes can be mapped out by all relevant stakeholders and discussed.
• Support: Tools that rely solely on community support and documentation might not be suitable for complex, enterprise-level environments. Access to professional services and a support team can expedite onboarding and troubleshooting and minimize disruptions to your testing process.
• User reviews (G2): By considering user reviews, you can gain a more comprehensive understanding of how a tool performs in real-world scenarios, helping you make more informed decisions that align with your organization's needs and expectations. We included G2's database of user reviews and ratings in our research process. 

Best E2E testing tools: Top 7 list 

1. Leapwork

Leapwork is an AI-powered visual test automation platform, made for validating entire user journeys across enterprise systems. Leapwork scores highly on user-friendliness and support, which makes ramp-up and day-to-day management smoother for enterprise organizations. It supports E2E testing across various applications, including web and desktop.

• Cross-technology capabilities: Extensive (covers web, mobile, desktop, and virtual environments)
• Ease of use and scalability: Easy (intuitive visual platform, templates, flexible and scalable architecture with minimal maintenance, made for enterprise teams)
• Support: Dedicated support and professional services available 
• G2 rating: 4.5/5 

2. Selenium WebDriver 

Selenium is a popular choice because it’s free, is open source, and has a large user community. However, Selenium WebDriver is - as the name implies - designed for web application testing, not testing E2E business processes across other types of applications.  

• Cross-technology capabilities: Limited (web applications)
• Ease of use and scalability: Variable (depends on developer resources and familiarity with web technologies, lacks built-in collaboration features)
• Support: No dedicated support. Relies on community and online documentation
• G2 rating: 4.5/5

3. Katalon 

Katalon provides an automation solution for web, mobile, and desktop testing. Users can use the tool to carry out basic automation through its no-code interface, but it requires scripting for more complex scenarios, making it more suitable for technical users.

• Cross-technology capabilities: Extensive (covers web, mobile, and desktop applications)
• Ease of use and scalability: Easy to moderate (intuitive for developers, supports codeless automation but requires scripting for complex scenarios)
• Support: Dedicated support team 
  
• G2 rating: 4.4/5 

4. Tricentis Tosca 

Tricentis Tosca leverages AI to enhance the speed and stability of tests. It's designed to simplify the creation and maintenance of automated tests through an intuitive technical interface. Tricentis offers comprehensive training services but doesn’t offer live support.

• Cross-technology capabilities: Broad (covers web applications and mobile testing)
• Ease of use and scalability: Easy to moderate (smart features for fast test creation, but complex scenarios require deeper customization)
• Support: No dedicated support. Only training and support hub.
• G2 rating: 4.3/5

5. TestComplete by SmartBear 

TestComplete enables automated testing across multiple platforms and environments through scripting capabilities. It offers record and replay features, along with a flexible scripting language that accommodates testers of varying skill levels. TestComplete is supported through documentation, training, and community support.

• Cross-technology capabilities: Extensive (covers web, mobile, desktop, and virtual environments)
• Ease of use and scalability: Moderate (intuitive interface but requires coding, but can only handle complex scenarios with advanced scripting)
• Support: No dedicated support. Only training and support center.
• G2 Rating: 4.2/5

6. Ranorex Studio 

Ranorex Studio is an automation testing tool that facilitates testing for web, desktop, and mobile applications. The tool offers a blend of codeless test creation for beginners and customizable scripting options for advanced users. Ranorex Studio offers support through documentation, professional email support, and user community. 

• Cross-technology capabilities: Broad (covers web, desktop, and mobile platforms)
• Ease of use and scalability: Moderate to difficult (robust tools for managing complex test suites, but requires skilled technical resources)
• Support: Dedicated email support and community.
• G2 Rating: 4.2/5
  
  

7. Keysight Eggplant 

Eggplant is an AI-powered testing platform that works across multiple platforms. Its visual approach allows non-technical users to create and manage tests. However, some users have noted a steep learning curve and performance issues when dealing with large test suites.

• Cross-technology capabilities: Extensive (supports testing across web, desktop, mobile, and more)
• Ease of use and scalability: Easy to moderate (image-based approach suitable for non-technical users, but some find a steep learning curve)
• Support: No dedicated support. Only documentation and training.
• G2 Rating: 4.2/5

Ensure compatibility and consider total costs 

Each tool in this list has its own unique strengths, making each one suitable for different testing scenarios and requirements.

Most importantly, do ensure that the tool you’re considering can work with your applications in the E2E testing process.

It’s also crucial to also consider your team's technical proficiency, the types of journeys and business processes you're testing, and your maintenance capabilities.  

Looking beyond just the platform license costs to things like ramp-up costs and maintenance costs is key if you’re thinking strategically about which tool will provide the best ROI for your business.

Conclusion

E2E testing allows you to significantly decrease risks and ensure that your key business processes work as expected.

Whether you're a Product Owner or a QA Manager, you can breathe easier knowing your critical user journeys are working as expected.  

With E2E testing, you’re not just validating processes—you’re building confidence and reliability in your business.

Build out your E2E strategy with our Test Automation Strategy Checklist below: