Accurate Estimating with Relative Size Scale

Estimation is a touchy topic in software development projects. In this article, Grant Rule proposes a quick and easy guide to accurate early estimating of software project size, costs and viability based on clothing sizes: Small, Medium, Large, Extra Large.

The Rules Relative Size Scale uses terms familiar from clothing measurements (XXS – XXXL) to categorise projects into approximate size ranges. The ranges are derived from ISBSG benchmark data and other source. They provide a reliable quick reference to estimate effort, staffing and cost early in the software development life cycle. This approach can be calibrated to your local environment and it allows comparisons between your projects and others of similar size.