23ISO 25000-23Part 23 measurement record

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Annex B ยท thirty-one elements

The quality measure elements the draft names

Annex B lists thirty-one elements. Thirty are counts and one is a duration. They are the raw material of every measure in clause 6, and their names are public in the contents even though the annex text is not.

The list

  1. 01 Number of functions
  2. 02 Number of requirements
  3. 03 Number of failures
  4. 04 Number of faults
  5. 05 Number of hazards
  6. 06 Duration
  7. 07 Number of test cases
  8. 08 Number of restarts
  9. 09 Number of jobs
  10. 10 Number of tasks
  11. 11 Number of user actions
  12. 12 Number of user inputs
  13. 13 Number of data items
  14. 14 Number of records
  15. 15 Number of responses
  16. 16 Number of results
  17. 17 Number of user operations
  18. 18 Number of system operations
  19. 19 Number of languages
  20. 20 Number of software modules
  21. 21 Number of components
  22. 22 Number of interfaces
  23. 23 Number of information structures
  24. 24 Number of user interfaces
  25. 25 Number of interface items
  26. 26 Number of operational usage scenarios
  27. 27 Number of events
  28. 28 Number of input conditions
  29. 29 Number of hardware environments
  30. 30 Number of software environments
  31. 31 Number of operational environments

What an element is

A quality measure element is a property plus the measurement method that quantifies it, optionally transformed by a mathematical function. The definition is in clause 3.9, and the format is the subject of ISO/IEC 25021.

Why the list is mostly counts

Software quality is largely measured by counting defined things and relating the counts. That is why the draft can define a quality measure as a function of two or more elements: the elements are the counts, and the function turns them into a rate, a ratio or a percentage.

What the annex does not publish

Which element feeds which measure family. This site publishes a worked example on each family page and labels it as ours. The draft's own assignment is behind the paywall.

Use the list as a checklist

If a measure in your register cannot be decomposed into elements from this list, or into named local elements, it is a number with no provenance. That is the first thing the free check asks about.

Run the check

Counts of work, counts of failure, counts of context

The thirty-one fall into three groups. Counts of work describe the size of the thing measured: functions, requirements, tasks, jobs, test cases, operational usage scenarios. Counts of failure describe what went wrong: failures, faults, hazards, restarts. Counts of interaction and environment describe the population and the conditions: user actions, inputs, operations, responses, results, data items, records, interfaces, modules, components, environments, languages. Duration is the one time element, and it is what turns a count into a rate.

Read the element page Read Annex B

The rules this is built from

Read from the real rules, not invented.

Every line points to the public ISO record or the free preview it came from, so you can check it yourself.

  • Read from the real rules
  • 63 record pages behind it
  • 116 public headings checked
  • Check any line yourself

The measure set is read from the public contents; the model table is read from the public 25010:2023 model. Where the draft text is not public, the page says so instead of filling the gap.

Nothing here is guessed while you wait. Each page is written from the public record and points to the exact page it came from. Record updated 22 October 2026