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Critical Path Duration Calculator

Estimate project duration using PERT (Program Evaluation and Review Technique) with optimistic, most likely, and pessimistic time estimates. Ideal for project managers who need a statistically weighted schedule with a built-in buffer.

Optimistic Duration (days)

Most Likely Duration (days)

Pessimistic Duration (days)

Schedule Buffer

Fill in the required fields to see your result.

Project Management

Critical Path Duration Calculator

Sum the durations of three sequential tasks to estimate critical-path duration. Use it for very simple linear project sizing or as an introduction to the critical-path concept — for real projects with branching dependencies, use proper CPM software.

Task 1 Duration (days)

Task 2 Duration (days)

Task 3 Duration (days)

Fill in the required fields to see your result.

Key differences

	Critical Path Duration Calculator	Critical Path Duration Calculator
Category	Project Management	Project Management
Inputs required	4	3
Result	Expected Project Duration (days)	Critical Path Duration (days)
What it does	Estimate project duration using PERT (Program Evaluation and Review Technique) with optimistic, most likely, and pessimistic time estimates. Ideal for project managers who need a statistically weighted schedule with a built-in buffer.	Sum the durations of three sequential tasks to estimate critical-path duration. Use it for very simple linear project sizing or as an introduction to the critical-path concept — for real projects with branching dependencies, use proper CPM software.