Compare calculators

Both calculators run independently — change the inputs on either side to compare results.

Project Duration Estimator (PERT)

Estimate realistic task or project durations using the PERT three-point technique, which blends optimistic, most-likely, and pessimistic scenarios into a single weighted average. Use it whenever a single-point estimate feels too uncertain.

Optimistic Duration (days)

Most Likely Duration (days)

Pessimistic Duration (days)

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

	Project Duration Estimator (PERT)	Critical Path Duration Calculator
Category	Project Management	Project Management
Inputs required	3	3
Result	Expected Duration (days)	Critical Path Duration (days)
What it does	Estimate realistic task or project durations using the PERT three-point technique, which blends optimistic, most-likely, and pessimistic scenarios into a single weighted average. Use it whenever a single-point estimate feels too uncertain.	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.