Knowledge Center

What Is an Error Age and How to Define It?

An error age is the time interval when the error was detected and when it was fixed. In its turn, age testing is focused on calculating the percentage of the errors age, discovered in the software product system.

Performing error age calculation, it is important to remember following:

  • A time interval between detection and removal of error can be calculated in hours or days.
  • The detected bugs should be not only opened but also assigned to the appropriate person and confirmed.
  • The errors which were not confirmed will be not considered.

There are two ways to calculate the error age: by time and by phases. In order to define the bugs age by phases, it is necessary to deduct the phase number on which the error occurred from the phase number on which the error was detected. For instance, the following steps were determined for the project development:

  1. requirements development,
  2. designing,
  3. coding,
  4. module testing,
  5. integration checking,
  6. system testing,
  7. acceptance testing.

Suppose, the error was discovered at the step #4 (module checking) and the reasons for its occurrence are connected with the 2nd phase (system designing). Thus, the age of this error is 2 (4-2).

How to сalculate the error age by time?

  • Define exact time when the bug was found.
  • Fix time after its complete removal.
  • Subtract item #1 from item #2.

For example, conducting functional testing or performance testing, the specialist detected the bug on the 10th of April. This error was fixed on the 12th of April. This means that the age of this bug is 2 days.