Spiral Model

Spiral Model

A spiral model is a combination of an iterative and sequential linear process models. It allows for continuous enhancements to each incremental release of a prototype. The project repeatedly passes through four phases until the entire software is built. 

When to use a Spiral Model

A spiral model is used when a project is long, the risks need to be continuously evaluated, requirements are complicated, the software requires significant changes, and frequent releases are required.


  • Fast development
  • Larger projects and software are handled strategically
  • Proper risk evaluation
  • Control of phases in development
  • Features are added systematically
  • Early production of software
  • Customer feedback and changes are implemented faster


  • Expertise is required for risk analysis
  • Not beneficial for small projects
  • Spiral might continue infinitely
  • More documentation with the intermediate phases
  • Costly for small projects