Difference Between PERT and CPM

Main Difference

The project management is a crucial task in every business enterprise. The poor management can cause delay or the surpassing of the amount of that product than the prescribed budget, which results in the loss and shame to the company. So whenever the company and organizations are up to the project, they try statistical methods to make sure that the work is done within the due time and the cost gets managed within the allocated budget. Project Management and Review Technique (PERT) and Critical Path Method (CPM) are two statistical techniques that make sure the fast and effective completion of the project. Both these techniques are quite different from each other as CPM is the cost-based technique, whereas the PERT is the time-based technique. The CPM is the method that is used in the products that have predictable tasks; just like construction projects. On the other hand, the PERT is the method that that is used in the unpredictable tasks; just like development and research projects.

Comparison Chart

PERTCPM
ApplicablePERT is only the time-based technique.CPM is the both time and cost-based technique.
Nature of the ProjectPERT is quite handy when dealing with the unpredictable tasks and activities as it evaluates the total time required to complete the project with dealing with the uncertainties if any.CPM is highly recommended by the experts for the conventional projects that comprise of the predictable tasks and activities.
Project ExamplePERT is useful for the research and development project as they comprise of the unpredictable tasks and activities.CPM is useful for the construction projects as it comprises of the predictable tasks and activities.
Nature of the TechniquePERT is the probabilistic project management tool.CPM is the deterministic management tool.

What is PERT?

PERT is the statistical management technique, which is applied to make sure the projects are done within the due time. This technique was first introduced in the 1950’s, with the aim to managing the time and the cost of the project. It is quite handy when dealing with the unpredictable tasks and activities as it evaluates the total time required to complete the project with dealing with the uncertainties if any. The projects like reach and development can witness the unpredictable hurdles, this technique makes sure that these uncertainties are controlled in such a manner that they don’t have any effect on the cost and the time limit allotted for that project. When the project is up, using the PERT technique, planning, scheduling, controlling, coordinating and controlling of the unpredictable activities is done. Most primarily, using this technique three estimates for the time required are made; the most promising, the most probable, and the most unfavorable. The technique is pivotal in accessing the time required, which leads to the completion of the project before the due date. The activities are also divided and time required for each of it is also estimated, and following it the critical path (longest path connecting all tasks) is evaluated.

What is CPM?

CPM is the statistical management technique, which is equally pivotal in managing both the time and the cost of the project. The CPM is useful for the projects which have quite the predictable activities like the construction projects. It is both the time and the cost-based algorithm which gives a clear estimate of the cost required to wrap up the project within the given time. It also decides that what aspect of the project should be reduced or increased when the trade-off is needed. This technique came in practice in the late 1950’s; it assesses the earliest and the latest possible starting time for each of the task divided in the entire project. The path is defined as the sequence of activities in the network, and the critical path is the one with the highest length. The experts highly recommend CPM for the conventional projects that comprise of the predictable tasks and activities.

PERT vs. CPM

  • CPM is the both time and cost-based technique, whereas the PERT is only the time-based technique.
  • PERT is quite handy when dealing with the unpredictable tasks and activities as it evaluates the total time required to complete the project with dealing with the uncertainties if any. On the other hand, CPM is highly recommended by the experts for the conventional projects that comprise of the predictable tasks and activities.
  • CPM is useful for the construction projects as it comprises of the predictable tasks and activities. Contrary to this, PERT is useful for the research and development project as they comprise of the unpredictable tasks and activities.
  • The CPM is the deterministic management tool, whereas PERT is the probabilistic project management tool.

Comparison Video

YouTube video