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Verification & Validation in software testing

Examine the principles of software validation and verification. Learn about their critical roles in ensuring reliable, high-quality software development and how these procedures work together to promote user satisfaction and product performance.

Written byMatt Valley
Published OnSat Jul 31 2021
Last UpdatedFri Feb 16 2024

Ensuring software products’ stability and quality is critical in the ever-changing world of software development. This is where the critical Verification and Validation (V&V) methods, which are the foundation of software testing, are implemented. These procedures are critical to the software development lifecycle (SDLC) since they ensure that the program fits the end user’s needs and specifications. Verification and validation terms are commonly used in software engineering and software testing. This article will go through both verification and validation concepts in software engineering and software testing.

Understanding Verification and Validation

Although they are sometimes used synonymously, verification and validation are two important components of software testing that serve separate functions:

  • Verification closely investigates the software development process to ensure the product meets the required specifications. It involves confirmation and documentation, which includes non-executive code-related tasks such as reviews, inspections, and analyses.
  • On the other hand, Validation compares the final product to the user’s requirements. The software must be run dynamically to ensure it performs properly in the operating environment.

Detailed Exploration of Verification

Verification prioritizes prevention as the first line of defence against flaws. It involves a detailed analysis of software artifacts such as test cases, code, and design documentation. Techniques consist of:

  • Reviews and Inspections: Official inspections of the code and documentation.
  • Walkthroughs: Group reviews with the goal of identifying errors.
  • Static Analysis: Without running the code, automated tools check it for possible errors.

In-Depth Look at Validation

Validation, which focuses on functionality and performance, ensures that the software product meets consumers’ expectations. Important actions for validation include:

  • Functional Testing: Verifies software actions against defined specifications.
  • Non-Functional Testing: evaluates security, usability, and performance factors.
  • User Acceptance Testing (UAT): Verifies that the program meets the user’s requirements and expectations.

Role of Automation in Verification and Validation

In V&V, automation transforms the field by increasing coverage and efficiency. Automated testing systems can run a set of tests repeatedly to ensure that code modifications don’t introduce new flaws. Popular tools that meet many testing requirements, from unit testing to user interface testing, are Selenium, JUnit, and TestComplete.

Best Practices for Implementing Verification and Validation

A structured approach is required for effective V&V:

  • Early Integration: Include V&V early and throughout the SDLC.
  • Clear Documentation: Maintain comprehensive documentation to provide transparency and clarity.
  • Continuous Communication: Facilitate ongoing communication among developers, testers, and stakeholders.

Challenges and Solutions in Verification and Validation

There are various challenges to overcome while implementing V&V, including ensuring complete test coverage and adapting to changing requirements. The answers include leveraging automated testing to test additional areas, adopting agile methodologies, and creating a feedback-driven culture.

Verification vs. Validation

The table below compares verification and validation to give you a better picture of both concepts and the area they cover.

ProcessCompare software with the requirements & specifications.
Find the inconsistencies and fix them.
Make sure the product satisfies customer needs at any stage
PurposeAre we building the product right?Are we building the right product?
Development activitiesCode reviews, style checks, static analysis, walkthroughs, inspectionsprototyping, user interviews, goal analysis
Test activitiesUnit testing, integration testing, functional and non-functional testingusability testing, beta testing, customer acceptance testing
TargetsDifferent software components, architecture, infrastructure, databaseThe actual product
Waterfall developmentThroughout the developmentAfter development is completed
Agile developmentThroughout the developmentBefore, throughout and after development
Parties involvedEngineers, Testers, QAProduct owners, UX, testers, QA

Verification vs. Validation in software testing

As we discussed earlier, both verification and validations are done through automated and manual software testing. With that said, there are areas of testing that can be considered part of both verification and validation. In the diagram below, both beta & regression testing can be considered part of verification and validation.

Verification vs Validation in software testing

API verification using Testfully

Using Testfully, our customers exercise API testing to verify the correctness of their API across dev, staging, UAT, pre-prod, and production environments. Moreover, Testfully allows our customers to run the test cases in the background for API monitoring purposes. The below short video gives you a quick demo of Testfully for API testing & monitoring.


Finally, verification and validation are critical processes in software testing, with each playing a distinct role in guaranteeing the creation of high-quality software products. Verification guarantees that the product is constructed correctly by adhering to specifications, whereas validation validates that the product built meets user needs and expectations. Together, they form a comprehensive method for identifying and resolving possible issues early on, improving software reliability and performance. Emphasizing both phases in software development projects ensures that the end result not only meets technical criteria but also provides a satisfactory user experience.

Frequently Asked Questions

We got an answer for your questions

  • What is verification?

    Verification is the process of evaluating whether or not a software product or system complies with the requirements and specifications. In general, verification is concerned with: are we building the product right?

  • What is validation?

    Validation is evaluating whether or not a software product or system meets the needs of the customers. In general, validation is concerned with: are we building the right product?

  • What kind of activities are done during verification?

    Development activities include Code reviews, style checks, static analysis, walkthroughs, inspections. Software testing activities include Unit testing, integration testing, functional and non-functional testing.

  • What kind of activities are done during validation?

    Development activities include: prototyping, user interviews, goal analysis. Software test activities include usability testing, beta testing, customer acceptance testing.

  • What do we test as part of validation?

    The actual product (developed or intended to be developed in future).

  • What do we test as part of verification?

    Software, architecture, infrastructure, source code, and databases.

  • Do verification and validation overlap?

    During development, they don’t often overlap, but it’s not common to see verification and validation overlap during software testing.

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