Software Size Estimation: Practical Models and their Applications in Various Phases of the SDLC

Estimating software size has been one of the highly researched topics over the past few decades. Due to the unpredictable nature of many factors associated with software development projects and ever-changing technological complexity, the topic still draws widespread attention within the software engineering domain. This paper briefly discusses few estimation models that can be practically applied to estimate software metrics such as size, effort, and time, without getting involved into mathematical complexity by a project manager. We also discuss the pros and cons of these models. We further map the applicability of these models in various phases of the software development life cycle. Finally, we implement two of these models to develop a user interface that can be used repeatedly or as necessary to estimate the software metrics during the major stages of its developmental life cycle, and adjust the schedule as necessary