Gantt Chart vs PERT Chart

Difference Between Gantt Chart vs PERT Chart in Tabular Form

Gantt Chart

Advantages :
a) Clarity : Stakeholders throughout an organization can easily understand where teams are in a process while grasping the ways in which independent elements come together toward project completion.
b) Communication : Teams can use Gantt charts to replace meetings and enhance other status updates.
c) Motivation : Some teams or team members become more effective when faced with a form of external motivation.
Disadvantages :
a) They can become extraordinarily complex. Except for the most simple projects, there will be large numbers of tasks undertaken and resources employed to complete the project.
b) The size of the bar does not indicate the amount of work. Each bar on the chart indicates the time period over which a particular set of tasks will be completed.
c)Difficult to see on one sheet of paper. The software products that produce these charts need to be viewed on a computer screen, usually in segments, to be able to see the whole project.
d) They need to be constantly updated. As you get into a project, things will change. If you’re going to use a Gantt chart you must have the ability to change the chart easily and frequently.

PERT Chart

Advantages :
a) PERT charts give a graphical representation of a project, broken down into its activities. The project team sees all the steps needed to complete the project. Each team member also clearly sees her own activities and responsibilities.
b)  PERT charts also outline the relationships and dependencies between individual project activities, helping you understand the order of work. For example, charts show which parts of a project to complete before you can start working on others.
Disadvantages :
Complicated Charts
PERT charts can be complicated and confusing, with hundreds or even thousands of tasks and dependency relationships, as noted by the University of Pittsburgh. This is especially true of very large projects. PERT diagrams can be expensive to develop, update and maintain.
Prediction Inaccuracies
PERT charts depend on the ability to predict precise time frames for multitudes of tasks. Complicated projects involving many activities and suppliers can make this prediction difficult, as explained by U.S. Legal Definitions. Unexpected events occur, and sometimes the original estimate of time needed for specific steps was inaccurate. PERT works best in projects where previous experience can be relied on to accurately make these predictions.