Automation Testing Manual Testing
Automation testing perform the same operation each time Manual testing is not reliable. Using this method test execution is not accurate all the time.
Automation testing is very much helpful regressions in testing where code changes frequently. To execute the test cases first time using manual testing will be very much useful. But it is not sure that it will catch the regression defects under frequently changing requirements.
Automation testing will be useful to execute the set of test cases frequently. Manual testing will be useful when the test case only needs to run once or twice.
After making Automation test suites, fewer testers required to execute the test cases. To execute the test cases every time tester requires the same amount of time.
Automation testing can also be done on different machine with different OS platform combination, concurrently. Using manual testing,testing on different machine with different OS platform combination is not possible, concurrently. To execute such task different testers are required.
Using Automation testing, testers can test complicated application too. It does not involve in programming task to fetch hidden information.
Automation runs test cases significantly faster than human resources. Manual testing is slower than automation. Running tests manually can be very time consuming.
Some time it is not helpful in UI testing It is very much helpful in UI testing
Automation testing is very useful for automating the Build Verification Testing (BVT) & it is not mundane and tiresome. To execute the Build Verification Testing (BVT) is very mundane and tiresome in manual testing.
Initial cost of automation testing is more than manual testing but useful always. Manual testing requires less cost than automation.