Difference between acceptance test and functional test

Question

What is the real difference between acceptance tests and functional tests   What are the highlights or aims of each  Everywhere I read they are ambiguously similar

User · Answer

Acceptance testing is just testing carried out by the client  and includes other kinds of testing    Functional testing   this button doesn t work  Non-functional testing   this page works but is too slow    For functional testing vs non-functional testing  their subtypes  - see my answer to this SO question

User · Answer

Audience   Functional testing is to assure members of the team producing the software that it does what they expect   Acceptance testing is to assure the consumer that it meets their needs    Scope   Functional testing only tests the functionality of one component at a time   Acceptance testing covers any aspect of the product that matters to the consumer enough to test before accepting the software  i e   anything worth the time or money it will take to test it to determine its acceptability       Software can pass functional testing  integration testing  and system testing  only to fail acceptance tests when the customer discovers that the features just don t meet their needs   This would usually imply that someone screwed up on the spec   Software could also fail some functional tests  but pass acceptance testing because the customer is willing to deal with some functional bugs as long as the software does the core things they need acceptably well  beta software will often be accepted by a subset of users before it is completely functional

User · Answer

In my view the main difference is who says if the tests succeed or fail   A functional test tests that the system meets predefined requirements  It is carried out and checked by the people responsible for developing the system   An acceptance test is signed off by the users  Ideally the users will say what they want to test but in practice it is likely to be a sunset of a functional test as users don t invest enough time  Note that this view is from the business users I deal with other sets of users e g  aviation and other safety critical might well not have this difference

User · Answer

I like the answer of Patrick Cuff  What I like to add is the distinction between a  test level and a test type which was for me an eye opener   test levels  Test level is easy to explain using V-model  an example   Each test level has its corresponding development level  It has a typical time characteristic  they re executed at certain phase in the development life cycle    component unit testing    verifying detailed design component unit integration testing    verifying global design system testing    verifying system requirements system integration testing    verifying system requirements acceptance testing    validating user requirements   test types  A test type is a characteristics  it focuses on a specific test objective  Test types emphasize your quality aspects  also known as technical or non-functional aspects  Test types can be executed at any test level  I like to use as test types the quality characteristics mentioned in ISO IEC 25010 2011    functional testing reliability testing performance testing operability testing security testing compatibility testing maintainability testing transferability testing   To make it complete  There s also something called regression testing  This an extra classification next to test level and test type  A regression test is a test you want to repeat because it touches something critical in your product  It s in fact a subset of tests you defined for each test level  If a there s a small bug fix in your product  one doesn t always have the time to repeat all tests  Regression testing is an answer to that

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The relationship between the two  Acceptance test usually includes functional testing  but it may include additional tests  For example checking the labeling documentation requirements   Functional testing is when the product under test is placed into a test environment which can produce variety of stimulation  within the scope of the test  what the target environment typically produces or even beyond  while examining the response of the device under test   For a physical product  not software  there are two major kind of Acceptance tests  design tests and manufacturing tests  Design tests typically use large number of product samples  which have passed manufacturing test  Different consumers may test the design different ways   Acceptance tests are referred as verification when design is tested against product specification  and acceptance tests are referred as validation  when the product is placed in the consumer s real environment

User · Answer

Functional Testing  Application of test data derived from the specified functional requirements without regard to the final program structure  Also known as black-box testing   Acceptance Testing  Formal testing conducted to determine whether or not a system satisfies its acceptance criteria   enables an end user to determine whether or not to accept the system

User · Answer

The difference is between testing the problem and the solution  Software is a solution to a problem  both can be tested   The functional test confirms the software performs a function within the boundaries of how you ve solved the problem  This is an integral part of developing software  comparable to the testing that is done on mass produced product before it leaves the factory  A functional test verifies that the product actually works as you  the developer  think it does   Acceptance tests verify the product actually solves the problem it was made to solve  This can best be done by the user  customer   for instance performing his her tasks that the software assists with  If the software passes this real world test  it s accepted to replace the previous solution  This acceptance test can sometimes only be done properly in production  especially if you have anonymous customers  e g  a website   Thus a new feature will only be accepted after days or weeks of use   Functional testing - test the product  verifying that it has the qualities you ve designed or build  functions  speed  errors  consistency  etc    Acceptance testing - test the product in its context  this requires  simulation of  human interaction  test it has the desired effect on the original problem s

User · Answer

Acceptance testing          is black-box testing performed on a system  e g  software  lots of manufactured mechanical parts  or batches of chemical products  prior to its delivery    Though this goes on to say      It is also known as functional testing  black-box testing  release acceptance  QA testing  application testing  confidence testing  final testing  validation testing  or factory acceptance testing   with a  citation needed  mark   Functional testing  which actually redirects to System Testing       conducted on a complete  integrated system to evaluate the system s compliance with its specified requirements  System testing falls within the scope of black box testing  and as such  should require no knowledge of the inner design of the code or logic    So from this definition they are pretty much the same thing   In my experience acceptance test are usually a subset of the functional tests and are used in the formal sign off process by the customer while functional system tests will be those run by the developer QA department

User · Answer

In my world  we use the terms as follows   functional testing  This is a verification activity  did we build a correctly working product  Does the software meet the business requirements    For this type of testing we have test cases that cover all the possible scenarios we can think of  even if that scenario is unlikely to exist  in the real world   When doing this type of testing  we aim for maximum code coverage  We use any test environment we can grab at the time  it doesn t have to be  production  caliber  so long as it s usable   acceptance testing  This is a validation activity  did we build the right thing  Is this what the customer really needs    This is usually done in cooperation with the customer  or by an internal customer proxy  product owner   For this type of testing we use test cases that cover the typical scenarios under which we expect the software to be used  This test must be conducted in a  production-like  environment  on hardware that is the same as  or close to  what a customer will use  This is when we test our  ilities     Reliability  Availability  Validated via a stress test  Scalability  Validated via a load test  Usability  Validated via an inspection and demonstration to the customer  Is the UI configured to their liking  Did we put the customer branding in all the right places  Do we have all the fields screens they asked for  Security  aka  Securability  just to fit in   Validated via demonstration  Sometimes a customer will hire an outside firm to do a security audit and or intrusion testing  Maintainability  Validated via demonstration of how we will deliver software updates patches  Configurability  Validated via demonstration of how the customer can modify the system to suit their needs    This is by no means standard  and I don t think there is a  standard  definition  as the conflicting answers here demonstrate  The most important thing for your organization is that you define these terms precisely  and stick to them

User · Answer

The answer is opinion  I worked in a lot of projects and being testmanager and issuemanager and all different roles and the descriptions in various books differ so here is my variation   functional-testing  take the business requirements and test all of it good and thorougly from a functional viewpoint   acceptance-testing  the  paying  customer does the testing he likes to do so that he can accept the product delivered  It depends on the customer but usually the tests are not as thorough as the functional-testing especially if it is an in-house project because the stakeholders review and trust the test results done in earlier test phases   As I said this is my viewpoint and experience  The functional-testing is systematic and the acceptance-testing is rather the business department testing the thing

User · Answer

They are the same thing    Acceptance testing is performed on the completed system in as identical as possible to the real production deployement environment before the system is deployed or delivered   You can do acceptance testing in an automated manner  or manually

[testing] Difference between acceptance test and functional test?

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