Early Software Sizing with COSMIC: Experts Guide

May 2020

Abran, A., Vogelezang, F.W. (eds.)

The COSMIC method provides a standardized way of measuring a functional size of software. In practice, it is sometimes sufficient or necessary to only approximate a functional size:

  • early in the life of a project, before the Functional User Requirements (FUR) have been specified down to the level of detail where the precise size measurement is possible;
  • when there is insufficient time or resources to measure using the standard method and a quick approximate size will be acceptable;
  • when the quality of the documentation of the actual requirements is not good enough for precise measurement.

The purpose of this Guide is to describe the current state of the art regarding early or rapid COSMIC functional size measurement using approximation techniques. This document describes several approximation techniques with their pros and cons, their recommended area of application and their validity.
The reader is assumed to be familiar with the standard COSMIC method. For those who need to use approximation techniques in practice, see the: Early Software Sizing with COSMIC: Practitioners Guide.


in Early and Rapid Functional SizeGuidelines Tags: Approximate sizingapproximation