Monday, January 20, 2014

Defect Density!

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 image


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.