Quality Testing

Quality is delighting customers

# How to calculcate defect leakage? and Explian with live example?

How to calculcate defect leakage

Please comment is my understanding is correct

The defects  which we are unable to find during the system testing or UAT  and it occurs in production it is called defect leakage.

It is calculated as

(Number of defects slipped)/(Number of defects received-Number of defects withdrawn)*100

Suggest a better answer regarding the same..

Views: 42255

### Replies to This Discussion

I would calculate it as followed:

Number of Defects slipped / (Number of Defects raised - Number of Defects withdwawn)

Example: In production the customer raises 21 issues, during your tests 267 Issues were reported but there were 17 invalid defects (p.e. because of wrong tests? mistake by tester, error in testenvironment...)

Then your Defect Leakage Ratio would be:

[21/(267-17)] x 100 = 8,4%

kr

Thanks for explaining it with the example Peter..
Defect leakage: The product delivered in client environment after that defect identified by client or end use and we gets the feedback is called defect leakage. This Defect Leakage is also called as Bug Leak.

Defect leakage ratio: Defect leakage ratio defines time mapping between defects found and resolved is called defect leakage ratio.

Thanks Peter for your perfect example.

Example: In production the customer raises 21 issues, during your tests 267 Issues were reported but there were 17 invalid defects (p.e. because of wrong tests? mistake by tester, error in testenvironment...)

----INVALID in the sense bugs which are marked as only INVALID or it counts to DUPLICATE,WONTFIX etc....

kr

Thanks for explaining it with the example Peter..
Defect leakage: The product delivered in client environment after that defect identified by client or end use and we gets the feedback is called defect leakage. This Defect Leakage is also called as Bug Leak.

Defect leakage ratio: Defect leakage ratio defines time mapping between defects found and resolved is called defect leakage ratio.

Thanks Peter for your perfect example.

## Videos

• ### Selenium2Maven.avi

Added by harry lei

• ### How to create python webdriver scripts?

Added by harry lei

">

Invalid Bugs do include unable to reproduce bugs and suspended bugs?

As per practices of software testing company, defect leakage means some issue or brokerage observed in the application at Production even if it is release after testing from QA, it means some leakage or gap is found in the application even after testing efforts from QA. It can be of any type either UI or functionality.

For e.g: If any particular application is under QA observation so that QA can test its complete functionality as per the requirement provided by client and after QA sign off to the client, client releases that into the Production but after release some kind of bug/issue is identified by end users then it will be considered as Defect leakage.

Percentage of defect leakage can be measured using following formula:
Defect Leakage(%)= (No. of defects identified by end user after release / Total no. of valid defects encountered by QA while testing the application before release)*100
If 45 defects were found at the production site by the end users and 150 defects were found during the whole QA process before releasing it to production. So, the defect leakage would be = (45/150)*100 = 30%