Defect Density is the number of confirmed defects detected in software/component during a defined period of development/operation divided by the size of the software/component.
The ‘defects’ are:
- confirmed and agreed upon (not just reported).
- Dropped defects are not counted.
The period might be for one of the following:
- for a duration (say, the first month, the quarter, or the year).
- for each phase of the software life cycle.
- for the whole of the software life cycle.
The size is measured in one of the following:
- Function Points (FP)
- Source Lines of Code
DEFECT DENSITY FORMULA
For comparing the relative number of defects in various software components so that high-risk components can be identified and resources focused towards them.
For comparing software/products so that quality of each software/product can be quantified and resources focused towards those with low quality.