Validation and Verification
Validation checks that data is sensible and in the right format, while verification checks it was entered correctly.
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Validation checks that data is sensible and in the right format, while verification checks it was entered correctly.
- Range checks and length checks
- Double entry verifies data
- Validation cannot guarantee correctness
🧠 Quick quiz
Three questions. Score 2 or more to complete the topic.
What is Validation and Verification?
Within Computer Science, which covers algorithms, programming, data, networks, hardware and safe, responsible use of technology, this topic explains Validation and Verification. Computing topics explain how software, hardware and data work, with diagrams and models that show each step in order.
Check that you can explain Validation and Verification in your own words and give one example from everyday life. If you can do that, you have understood the core idea.
Understanding Validation and Verification helps you design, test and explain programs, websites and systems, from small projects to exam questions.
Validation and Verification in detail
Validation checks that data entered is reasonable and sensible, but not necessarily correct. Types include range checks (age between 0 and 120), type checks (number, not text), length checks, presence checks (not empty), format checks (email contains @) and lookup checks.
Verification checks that data has been entered or transferred accurately, such as double entry (typing a password twice) or proofreading by visual check. A valid entry can still be wrong, since 17 is within range for age even if the true age is 71. Together they protect programs from bad data and reduce errors.
How the interactive helps you understand Validation and Verification
Click a step, or use the Previous and Next buttons, to move through the sequence one stage at a time. Auto-play moves on for you.
Before you change anything, predict the result. Then change one value at a time and check whether your prediction was right. This is a quick way to build a correct mental model of Validation and Verification.
Real-life uses and examples
- Explain Validation and Verification to someone new to computing by comparing it to a familiar process.
- Trace through a process that uses Validation and Verification to check what it does step by step.
- Recognise Validation and Verification in an app or device you use every day.
Common mistakes to avoid
- Using the term without being able to say what the computer actually does.
- Testing only the normal case and forgetting the edge cases.
- Learning the definition without testing it. Use the quiz and the interactive to check that you can apply the idea.
Frequently asked questions about Validation and Verification
What is Validation and Verification?
Validation checks that data is sensible and in the right format, while verification checks it was entered correctly.
What are the most important points about Validation and Verification?
The main points are: Range checks and length checks; Double entry verifies data; Validation cannot guarantee correctness.
Why is Validation and Verification useful?
Understanding Validation and Verification helps you design, test and explain programs, websites and systems, from small projects to exam questions.
How can I practise Validation and Verification?
Open the interactive at the top of this page and change the controls one at a time. Predict the result before each change, then take the three-question quiz. A score of two or more marks the topic as complete on this device.
Which topics are related to Validation and Verification?
Related topics in Computer Science include Searching Algorithms, Recursion, Programming Languages.