| Verification | Validation |
| Are we building the system right? | Are we building the right system? |
| Verification is the process of evaluating products of a development phase to find out whether they meet the specified requirements. | Validation is the process of evaluating software at the end of the development process to determine whether software meets the customer expectations and requirements. |
| The objective of Verification is to make sure that the product being develop is as per the requirements and design specifications. | The objective of Validation is to make sure that the product actually meet up the user’s requirements, and check whether the specifications were correct in the first place. |
| Following activities are involved in Verification: Reviews, Meetings and Inspections. | Following activities are involved in Validation: Testing like black box testing, white box testing, gray box testing etc. |
| Verification is carried out by QA team to check whether implementation software is as per specification document or not. | Validation is carried out by testing team. |
| Execution of code is not comes under Verification. | Execution of code is comes under Validation. |
| Verification process explains whether the outputs are according to inputs or not. | Validation process describes whether the software is accepted by the user or not. |
| Verification is carried out before the Validation. | Validation activity is carried out just after the Verification. |
| Following items are evaluated during Verification: Plans, Requirement Specifications, Design Specifications, Code, Test Cases etc, | Following item is evaluated during Validation: Actual product or Software under test. |
| Cost of errors caught in Verification is less than errors found in Validation. | Cost of errors caught in Validation is more than errors found in Verification. |
| It is basically manually checking the of documents and files like requirement specifications etc. | It is basically checking of developed program based on the requirement specifications documents & files. |
Conclusion on difference of Verification and Validation in software testing:
- Both Verification and Validation are essential and balancing to each other.
- Different error filters are provided by each of them.
- Both are used to finds a defect in different way, Verification is used to identify the errors in requirement specifications & validation is used to find the defects in the implemented Software application.
source: http://www.softwaretestingclass.com/difference-between-verification-and-validation/