What is Software Testing Life Cycle (STLC)?

GOKUL M S | December 01, 2022

What is Software Testing Life Cycle (STLC)?

STLC is an integrated component of SDLC (Software Development Life Cycle), gone are the times when any software was made based on its requirements, and the moment it was used when it got released to the customer after being completed by the development team. But now testing has become a distinct phenomenon during and after the development of software. No software is released to the customer without comprehensive testing by QC or the testing team in the organization.

The method may vary from product to product, customer to customer, and organization to organization. There are certain aspects of the Software Testing Life Cycle. Software Testing Life Cycle (STLC) is a combination of specific activities done during the testing process to make sure software quality needs are met.


  • The execution phase is put together to bring out software of higher quality.
  • The STLC improves the stability and produces a desired or intended result and the progress of the testing process.
  • Easily understood and executed without consideration of the level of the testing process.
  • Tests are done on each module before proceeding with the next.
  • Upgrade the quality of the development process.
  • Enhance quality control all through the SDLC.
  • Ensuring that the Client, as well as the Users, receive a quality product.

The 6 Phases Of the STLC Model are:

  1. Requirement Analysis
  2. Test Planning
  3. Test Case Development
  4. Test Environment setup
  5. Test Execution
  6. Test Cycle Closure

1. Requirement Analysis

Requirement Analysis is the prime stage of STLC. In this stage, the testers identify all the testing requirements. The quality assurance professionals will interact with all the shareholders like system architects, end clients, business analysts, and so on. To verify and understand all the requirements in-depth.

2. Test Planning

A test plan outlines the master plan that will be used to test an application, the assets that will be used, the testing environment in which testing will be carried out, the obstacles of the testing, and the setup of the testing activities. The Quality Assurance Team head will be responsible for creating a Test Plan.

3. Test Case Development

The Test Case Development Phase involves the designing, verification, and rework of test cases & test scripts after the test plan is ready. primarily the test data is recognized then created and reviewed, and then reworked based on the preconditions. Then the QA team begins to do the development process of test cases for individual units.

4. Test Environment Setup

A test environment allows you to create similar environments whenever you need to test your product. It’s the key important tool for a testing engineer to be confident in the testing results.
A test environment delivers precise feedback about the quality and actions of the application under a test. which means that a test environment provides you with the mandatory setup to run your test cases.

Various test environments are:

  • The software is to be tested.
  • The Operating System, Database, and Test Server Test Data Network Configuration.
  • The device which hosts the software is to be tested.
  • Test relevant automation frameworks and tools.
  • Relevant Documentation: test cases, user manuals, business & customer requirements software to interface between system and applications.

5. Test Execution

Test execution is the process of executing the code and checking whether the expected and actual results are the same. Tests should be performed as per the described test cases. The entry criteria of this phase are the accomplishment of the Test Plan and the Test Cases Development phase, the test data should also be ready. The exit criteria need the successful validation or verification of all Test Cases. Test case execution and the defect summary report should be ready.

6. Test Cycle Closure

This is the final phase of the STLC, during which a test result report is developed. This report should sum up the entire testing process and come up with comparisons between expected results and actual results.

Entry Criteria and Exit Criteria

Entry criteria for testing can be described as special conditions or running activities that must be present before a process begins.” The Software Testing Life Cycle identifies the entry criteria requirement during each testing phase. It also determines the time interval of lead time to make the entry criteria element available to the process.

The inputs may be divided into two types:

  1. Received from the development
  2. Made the test phases at the final stage of STLC

The Exit Criteria are used to know whether a given test activity has been completed or not. Exit criteria can be described for all the test activities right from planning, specification, and execution. Exit criteria should be part of the test plan and should be decided in the planning stage itself.

The Difference Between SDLC Over STLC

  • SDLC decides all the standard phases which are involved during the software development process, but to improve the quality of the product the STLC process defines various activities.
  • In SDLC, the development team makes all levels of design plans, but In STLC, the tester designs the System Integration Test Plan.
  • In SDLC, real code is developed, and actual work takes place as per the design documents, whereas in STLC testing team creates the test environment and executes test cases.
  • The SDLC life cycle helps a team accomplish the software’s successful development whereas the STLC phase only ensures Software Testing.

Hence, STLC makes sure of lesser project costs and delivers on time as the testing team can expose bugs and deviations quickly by following the regular test process. Since each STLC phase has a clearly stated objective and deliverable so it helps in evaluating the progress with the different breakthroughs achieved in each different phase. We hope this blog was helpful for you, feel free to ask your doubts or questions about STLC our experts.

As a fast-growing company, Sanesquare Technologies offers the best Software Testing/Quality Testing services for Canada, the UK, the USA & other countries. Contact us if you need assistance with Software Testing Services.

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