Difference between Waterfall Model and Spiral Model

Last Updated : 23 May, 2024

The waterfall model and Spiral model are used in software development. Waterfall model is also known as the classical or linear model because it follows sequential stages while the spiral model does not follow the sequential stages it follows the evolutionary way. The amount of risk in the waterfall model is more as compared to the spiral model because the errors or risks are identified and refined after the completion of each stage.

What is Waterfall Model?

The waterfall model is a software development model used in the context of large, complex projects, typically in the field of information technology. It is characterized by a structured, sequential approach to project management and software development.

What is Spiral Model?

The Spiral Model is a Software Development Life Cycle (SDLC) model that provides a systematic and iterative approach to software development. In its diagrammatic representation, looks like a spiral with many loops. The exact number of loops of the spiral is unknown and can vary from project to project. Each loop of the spiral is called a phase of the software development process.

Difference between Spiral Model and Waterfall Model

There are some differences between these two models waterfall and spiral models which are given below:

Aspect	Waterfall Model	Spiral Model
Complexity	The Waterfall model is simple and easy.	The spiral model is a lot more complex.
Development Method	The waterfall model works in a sequential method.	While the spiral model works in the evolutionary method.
Risk Management	In the waterfall model errors or risks are identified and rectified after the completion of stages.	In the spiral model errors or risks are identified and rectified earlier.
Adoption	The waterfall model is adopted by customers.	While the spiral model is adopted by developers.
Project Size Suitability	The waterfall model is applicable for small projects.	While the Spiral model is used for large projects.
Planning	In waterfall model requirements and early stage planning is necessary.	While in spiral model requirements and early stage planning is necessary if required.
Flexibility to Change	Flexibility to change in waterfall model is Difficult.	Flexibility to change in spiral model is not Difficult.
Risk Level	There is high amount risk in waterfall model.	There is low amount risk in spiral model.
Cost	Waterfall model is comparatively inexpensive.	While cost of spiral model is very expensive.
Customer Involvement	Customer involvement is minimum in Waterfall Model	In the Spiral Model Customer involvement is high.
Maintenance	It requires least maintenance.	It requires typical maintenance.
Framework Type	It is based on linear framework type.	It is based on linear and iterative framework type.
Testing	Testing is done after the coding phase in the development life cycle.	Testing is done after the engineering phase in the development cycle.
Reusability	Reusability is extremely unlikely.	To a certain extent, reusability is possible.
Customer Control	Customer control over the administrator is very limited.	Customers have control over the administrator as compared to waterfall model.