Test data and its Importance

test data & its importance

Test data is specifically designed & documented input data for testing the software program. This input data is being fed into software application, which gets affected by the module during execution. Test data may be either positive to verify & validate the intended functioning of the system or negative to consider unexpected or unusual results and error handling mechanism of the application. Weakly designed data may not test all test scenarios, which may have an impact on the quality of software.

Test data can be filed in excel sheet, word document, text file and other similar files.

different test data files

All the data can be stored manually during test cases or by automatically from the files. In the verification of unexpected outputs or invalid inputs of software, test data is used. It is also utilized to stimulate the capacity of the application to attain the respond to unusual or unexpected inputs.

Types of Test Data

Test data could be any input element which may be used to test the software application from each different angle.

  • Blank Data: Data containing no files, to check error handling and exception throwing feature of the application.
  • Valid Set of Data: Appropriate and valid set of input data supported by the system to validate the expected functioning of the module or the application.
  • test data types

  • Invalid Set of Data: Unsupported data and files to ensure the error mechanism and managing feature of the application without getting crashed or break down.
  • Boundary Value Data: Testing application with the possible combinations of boundary value data within the scope of valid data for application's intended functioning and beyond which the application may likely to break.

How to create and prepare Test Data?


test data preparation

"First and the foremost approach that comes to mind is the manually creation of test data which may take large amount of time and efforts in preparing huge & complex sets of test data."

Copying Production Data to Testing Environment

test data preparation

"Already existing & available data used in the development environment may be brought into use for testing application in the testing environment."

Note:Input data may also be copied and used from the legacy client system.

Using Test Data Generator Tool

test data preparation

"One of the simplest and effective means of producing multiple variants of test input data to meet the need of each functional requirement."

To read more about the test data generation, read our article on test data generation.

Here are some rules to test the application's usefulness:

  • Favourable Test Data: Create test data, favourable to cost and time and also useful in identifying the bugs in all kinds of application.
  • Setting Right Data: For responding the data accurately, create the right data to ensure that application do meet as per perquisites and also to know that data is saved in rightly manner.
  • Setting Wrong Data:Defining and creating incorrect set of data is also important to check the behaviour of the application for negative values and so on.
  • Creating a Large Amount of Data: Large amount of test data would be needed to perform testing types like performance, load and stress testing and regression testing.
  • Negative Data: To check the creation of correct error message, the tester should execute the test cases in the default data set environment.


  • Performance test data: Here, test data being used is not for finding bugs but to assess the performance and the adaptability of the system under different situations. The testing sessions are should be reasonable and prudent. Such sort of data can be gathered from the client in the form of feedback.
  • Security Testing Data: For protecting the system from malicious impact, such tests are meant to perform. It mainly requires various test data for various reasons.
  • Confidentiality test data: It gives protection of data gave by the client.
  • Integrity test data: This makes certain that the information is provided by and to the system is totally authentic.
  • Authorization test data: Such test data decides the user's roles.
  • Authentication test data: It permits the user to login in numerous ways.

Read our related article Designing Your Test Data for Different Testing Types to gain more insight to the above stated test data designing.

Tips on Test Data

Tips on test data

"Proper data for testing gives ease to identify the serious flaws and make them correct. It is highly important for a tester to stay alert and keep a constant eye in each phase of the development cycle for the appropriate re-evaluation of test data."

Test Data is an important and inherited part of the software tests executions which drives out the behaviour, response and performance of each software module or of the whole software application, thereby requires sufficient & sincere amount of time and efforts while defining and designing test data.