Acceptance Testing: The Complete Guide to Types, Criteria, Tools, and Best Practices

1. Overview

Acceptance testing involves verifying an application’s acceptability from the user’s perspective, evaluating whether the software meets business requirements to determine its release readiness.

Throughout the Software Development Life Cycle (SDLC), testing is critical for verifying software applications for errors and quality. Multiple tests are executed during the entire SDLC process to ensure applications meet Software Requirement Specifications (SRS) before release. Among these tests, acceptance testing is conducted at the end of the SDLC, after system testing. This allows you to verify whether the developed software application is ready for end-user acceptance.

Acceptance testing focuses on validating application functionality from the end-user’s perspective without needing to understand the application’s internal structure or implementation details. Therefore, acceptance testing is considered a type of black-box testing. This approach helps ensure the application meets user requirements and expectations.

2. What Is Acceptance Testing?

Acceptance testing is a formal process that evaluates whether a system meets user needs, requirements, and business processes, enabling users and customers to determine system acceptance.

Acceptance testing, or pre-production testing, checks whether a software application meets acceptance criteria. It enables end-users and customers to decide whether to accept the system by formally testing user requirements, needs, and business processes. QA teams typically run acceptance tests in the final stage of the Software Testing Life Cycle (STLC).

However, business analysts, support teams, application users, and others may also participate in acceptance testing to provide feedback. They conduct acceptance testing under two different conditions: first, after system testing is complete, and second, before the application is available for actual use.

The main purpose of acceptance testing is to determine whether the developed software application is suitable for release. To achieve this goal, the testing team releases the software application to users after executing system tests. Users examine the application’s functionality for acceptance in a controlled environment that simulates real-world usage scenarios. The software application is released to the market after meeting acceptance criteria.

Acceptance testing aims to involve end-users of the developed software application in the testing process to seek feedback and make improvements. However, the purposes of acceptance testing are not limited to this. Below are some key purposes that demonstrate its importance.

3. Why Conduct Acceptance Testing?

In the software testing lifecycle, unit testing is performed first, followed by integration testing and system testing. Once completed, we finally conduct acceptance testing.

You might often encounter this question: When a software application undergoes multiple tests (unit, integration, then system) before final release, why do we need acceptance testing? This is because, in the later stages of application development, end-users should inspect its functionality and strive to ensure it meets their expectations.

Here are some additional reasons why end-users and testers should conduct acceptance testing:

• Ensure the software application’s reliability meets user requirements.
• Verify the software application meets quality standards and is ready for release.
• Identify defects and issues before releasing the software to end-users, thereby reducing the risk of any additional post-release testing costs by fixing bugs and errors promptly.
• Verify the software application works as intended, providing a positive user experience.
• Ensure the software application integrates easily with other third-party tools and functions correctly across different browsers, devices, and operating systems.
• Seek feedback and insights to identify areas for improvement in requirements gathering and testing.
• Ensure the developed software application meets critical compliance and security standards.
• Discover bugs and errors in the software application during the functional testing phase.
• Examine the software application’s development and find areas for improvement.
• Obtain immediate feedback from end-users on the software application, enabling quick changes or modifications based on feedback.
• Execute acceptance testing without the risk of any issues or errors occurring after release.
• Ensure the developed software application is user-friendly, thereby increasing end-user satisfaction.

4. Types of Acceptance Testing

Acceptance testing is divided into several types to verify that a software application is tested against every critical acceptance area. To understand this, we need a good grasp of its different types.

The table below summarizes the seven types of acceptance testing:

4.1 User Acceptance Testing (UAT)

User Acceptance Testing (UAT) is conducted on a software application to determine its functionality based on user needs and perspectives. End-user-defined specifications are used to execute UAT to check if the application meets them. The purpose of UAT is to check the software application’s usability and whether it meets business objectives and is ready for release.

End-users or a representative group of users can be asked to test the software application to verify desired outcomes related to its functionality. To do this, test scenarios and test cases that end-users will use must be created to ensure intended functionality.

4.2 Business Acceptance Testing (BAT)

Business Acceptance Testing (BAT) is performed to verify the developed software application against business requirements. When executing BAT, focus on user stories and end-user views related to the software application’s functionality. This testing should not be skipped because an application that passes UAT may fail BAT. Therefore, ensure through BAT that business benefits (financial) and purposes are achieved.

To perform BAT, the testing team needs a good understanding of the domain and end-user business. However, this can be quite challenging due to changing market environments and technological advancements.

Therefore, you can use requirement changes as test scenarios to be executed in the software application. Hence, the importance of BAT should not be overlooked during the software application development process.

4.3 Contract Acceptance Testing (CAT)

Contract Acceptance Testing (CAT) is executed in a software application to test it against predefined and agreed-upon criteria in a contract. Here, contract means that when the software application is ready for release, acceptance testing should be conducted within a specific time frame, and all acceptance cases should be resolved.

A Service Level Agreement (SLA) is a contract that stipulates payment after the application meets all requirements and indicates whether the contract has been fulfilled. Additionally, it will define the test period, test areas, and scenarios for future bugs if encountered. Such contracts can be signed before the software application is released.

4.4 Regulations Acceptance Testing (RAT)

Regulations Acceptance Testing (RAT) is performed to ensure the developed software application complies with the rules and regulations set by the government of the country where the application will be released. This type of testing should be conducted for all applications because rules and regulations defined by governing authorities may vary from country to country.

For example, RAT can be executed to check whether a software application with a payment page complies with Payment Card Industry Data Security Standard (PCI DSS) requirements. Some of these might include access control, secure credit card data storage, and data encryption in transit.

4.5 Operational Acceptance Testing (OAT)

Operational Acceptance Testing (OAT) is part of non-functional testing, used to verify and check the operational readiness of a software application before it is released to the market. In other words, OAT is executed to verify whether the application meets operational requirements, user expectations, and performance standards.

Certain aspects of operational requirements, such as recoverability, maintainability, reliability, and compatibility, are tested in OAT. To meet such operational requirements, the effectiveness of the software application can be verified and validated in a real environment where it will be used. Therefore, the stability of the software application can be checked by executing OAT.

4.6 Alpha Testing

Alpha testing is performed by alpha testers, where the software application is tested in its development or testing environment. Based on alpha testers’ feedback and suggestions, the application’s usage is enhanced by fixing specific bugs. The main purpose of alpha testing is to evaluate the software’s overall performance, functionality, and usability in a controlled environment.

Once the software application successfully passes alpha testing by addressing any issues and bugs, it may proceed to beta testing, where it is tested by a larger group of users or testers in a more realistic environment.

4.7 Beta Testing

Beta testing is performed by end-users outside the development team to uncover any remaining bugs before the application is released to the market. In other words, beta testing validates the software application’s functionality in a more realistic environment considering comprehensive usage scenarios.

Through beta testing, any issues or bugs not discovered during alpha testing can be identified. This essentially checks the quality of the developed software application. Based on this, feedback is provided to the development team to make improvements to the application before release.

5. Acceptance Testing Criteria

When we run acceptance tests, several sets of predefined requirements for the application must be met without omission. This helps ensure a reliable and powerful software application. Let’s learn these in this section.

To run acceptance tests, a set of prerequisites for testing the software application must be met. These prerequisites and conditions are called acceptance criteria. They are a set of acceptable conditions or features within the developed software application that need to be accepted by the end-user.

Acceptance criteria serve as a checklist to verify the application and ensure its functionality performs as intended without any errors. Here is a list of acceptance criteria that should be prepared before software application development:

• Functional Requirements: The application should function as instructed by users and perform specific intended tasks.
• Performance Requirements: The application should meet all performance requirements specified by users, such as response time, availability (the percentage of time the application is up and accessible to users), and throughput (a measure of how much work the application can perform within a given time frame).
• Usability Requirements: The application should meet usability requirements such as user interface design and navigation.
• Security Requirements: The application should meet data privacy and integrity requirements.
• Compatibility Requirements: The application should be compatible with different browsers, platforms, and operating systems.
• Regulatory Requirements: The application should have regulatory requirements, such as compliance with rules and regulations set by national governing bodies.

However, specific criteria should be considered before and after acceptance testing, known as entry and exit criteria. Let’s understand these from the sections given below.

5.1 Entry and Exit Criteria for Acceptance Testing

Similar to other phases of software testing, acceptance testing also has entry and exit criteria. Entry and exit criteria are key elements of acceptance testing that help measure whether the testing process is clear, effective, and controlled.

Entry Criteria (Before Conducting Acceptance Testing)

Before conducting acceptance testing, the following criteria need to be verified:

• Is system testing complete?
• Have all major bugs or errors been fixed?
• Do user stories exist and are they easy to understand?
• Is the Requirements Traceability Matrix (RTM) updated?
• Does the acceptance testing platform exist?
• Is the test environment ready for acceptance testing, including hardware, software, and network configuration?

Exit Criteria (Before Completing Acceptance Testing)

Before completing acceptance testing, the following criteria must be verified:

• Have all acceptance tests been successfully executed and passed?
• Have major bugs and errors been fixed and retested?
• Are all acceptance criteria met?
• Have end-users signed off on the acceptance test results, indicating their approval of the application for production deployment?

6. Acceptance Testing Tools

To meet the above criteria, certain software testing tools can be used to run acceptance tests. They not only simplify the work and save time but also ensure the reliability of the software application.

The table below summarizes four popular acceptance testing tools:

Detailed Descriptions

• Selenium: It is an open-source testing framework for automated testing of web applications. It supports multiple programming languages such as Java, JavaScript, Python, Perl, C#, and more. Additionally, Selenium can test web application compatibility across various browsers, including Chrome, Firefox, Edge, and others.
• Cucumber: It is an automated testing framework based on the behavior-driven development approach, used for acceptance testing. Test scripts can be created in a natural language format, making them easily understandable by non-technical people.
• JMeter: It is one of the most popular tools for load testing, stress testing, and performance testing of web applications. It can simulate multiple user requests and measure application response time and throughput.
• SoapUI: It is an open-source tool for testing REST and SOAP web services. Test scripts can be easily created, automated tests executed, and web service responses verified.

7. Steps to Execute Acceptance Testing

Acceptance testing is a crucial part of the software development process. As the final testing phase, it is essential to execute tests accurately to ensure the software application meets users’ Software Requirement Specifications (SRS).

Therefore, following a structured approach that covers all possible scenarios and simulates the real-world usage of the software application is vital.

Here, we explain the steps to run acceptance testing:

Step 1: Requirements Analysis

In the first step, the testing team collects required documentation for the software application from end-users through direct communication or other means such as workshops. Some required documentation includes software requirement specifications, business requirement documents, use cases, workflow diagrams, and designed data matrices. It will provide clear scenarios for testing the software application.

During this phase, the testing team evaluates the required documentation against the software application’s objectives. The team analyzes the information and breaks it down into smaller, manageable units. At this point, it is essential to ensure the requirements are clear and concise.

After defining requirements, you must verify them in the next step. This can be done by reviewing the requirements with end-users to ensure they are correct and appropriate. Based on this, create acceptance criteria by addressing measurable and well-defined issues. Next, we proceed to create the test plan.

Step 2: Create Test Plan

The test plan is crucial as it provides a roadmap for the testing process, ensuring that all aspects of the software are thoroughly tested and meet acceptance criteria. It ensures the testing process is well-structured, organized, and comprehensive. To create a test plan, you must outline the attributes of the acceptance test plan as follows:

• Introduction
• Acceptance test category
• Operating environment
• Test case ID
• Test case title
• Test case objective
• Test procedure
• Test schedule
• Resources

Step 3: Test Case Design

Based on the test plan, the next step is to write test cases. Test cases are written by testers, covering all requirements and acceptance criteria. They should also simulate real-world scenarios and address all software functionalities.

Test cases must be prioritized based on their importance to the acceptance criteria defined in the test plan. This will ensure that the most critical functionalities are tested first. Thereafter, test cases should be reviewed and verified to ensure they are accurate and complete. One can document test cases in a test case repository, which is a centralized location for all test cases.

Step 4: Test Case Execution

After writing test cases, they must be executed in a controlled environment, such as a testing laboratory. You should set up a test environment that simulates the real environment where the software application will run and serve its target users. You should also ensure the availability of all test data and required software and hardware components.

During this phase, all acceptance test cases must be executed individually, and the results of each test case must be recorded. If a test case fails, report the result to developers for resolution. The acceptance test report should include the following attributes:

• Report number
• Summary of each test’s non-conforming results
• Summary of each test’s failure results
• Test log location
• Tester’s name and time of testing
• Summary of to-do list
• Approval decision

Step 5: Review Test Results

Once all test cases have been executed and defects resolved, test results must be reviewed. You should verify errors reported in the previous test cycle so that developers can fix them. Additionally, for failed test cases, you should retest them after fixes. This is a critical step in acceptance testing as it helps ensure defects are resolved and test cases are passed successfully.

The results of test case execution must be documented with all test case details. A review should then be conducted to determine whether the developed software application meets acceptance criteria. If the software application meets acceptance criteria, it can be released.

Step 6: Get Sign-off

When the software application successfully passes acceptance testing, it is important to seek sign-off from end-users. This will confirm that end-users are satisfied with the software application and that it meets acceptance criteria.

8. Challenges and Recommendations for Acceptance Testing

When executing acceptance testing, certain challenges are encountered that may create obstacles in the software release process. Testers should address such bottlenecks to eliminate any involved risks.

8.1 Lack of Clear Requirements

Acceptance testing is conducted based on SRS to ensure the developed software application operates as users expect.

However, one of the main challenges of acceptance testing is the lack of clear requirements from end-users. Without clear requirements, it is difficult to define the acceptance criteria the software application must meet to be accepted by users.

A lack of clear requirements can lead to confusion, delays, and rework, delaying software release and increasing software development costs. It may also fail to deliver a positive user experience.

Recommendation: Before starting acceptance testing, clear, specific, and measurable requirements must be gathered and documented.

8.2 Time and Resource Constraints

If the application has specific high-impact issues, acceptance testing can be time-consuming. Additionally, it may require significant software and hardware resources. However, time and resource constraints can be significant challenges when there is a tight deadline to release the software application. This can lead to shortcuts, errors, and poor test coverage.

Recommendation: Therefore, planning and allocating adequate time and resources for acceptance testing is essential to ensure thorough and effective execution.

8.3 Communication Gaps Between Teams

Acceptance testing is not only performed by testers but also by end-users, project managers, and others. They may have different priorities, expectations, and communication styles. Therefore, communication gaps in acceptance testing can be prevalent, which may create problems in completing the timely release of the software application.

Recommendation: Establishing effective communication channels and processes is essential to ensure all team members are informed, engaged, and coordinated. Regular meetings, status updates, and documentation build team communication and collaboration.

9. Acceptance Testing Best Practices

Effective acceptance testing is critical to successfully releasing software that meets user needs. Although there are some challenges with acceptance testing, as described below, we can improve it by incorporating best practices.

Here is a summary of some best practices for acceptance testing, providing guidance and strategies for teams to ensure a successful testing process:

• Testers, developers, end-users, project managers, and others should be involved in the early stages of the software development lifecycle. Obtaining clear requirements in advance and following them will help; software can be developed accordingly to meet SRS.
• Acceptance test cases should be well-defined, measurable, and specific. This will help ensure acceptance criteria are clear and the testing process is focused.
• The test environment should simulate real-world conditions of software application usage. This can help identify and resolve issues that may not be apparent in a simulated environment.
• Proper acceptance testing documentation should be in place, which must include information about test plans, test cases, and defect reports. Such documentation is important as it ensures accountability, traceability, and transparency.
• Regular communication and progress reports, including test results, defect reports, and other metrics, should be established. This helps build trust, facilitate collaboration, and resolve issues promptly.

10. Conclusion

Acceptance testing is a crucial part of the software development lifecycle. Its main focus is checking the quality and operation of the software application against user-specified expectations and requirements. This article has explained every step of acceptance testing that should be performed to deliver a user-friendly software application. We hope that with the right testing tools and techniques, you can streamline the testing process, identify problems early, and deliver a product that exceeds user expectations.