PM Tool

PERT Estimator

Interactive PMKHub tool for project professionals.

PMKHub Tools

Estimate expected activity duration and uncertainty from three-point estimates.

PERT

Use consistent time units.

Optimistic (O) Most Likely (M) Pessimistic (P)

Expected Duration — (O + 4M + P) ÷ 6

Std. Deviation — (P − O) ÷ 6

Variance — SD²

Approx. 95% Range — TE ± 2SD

Calculate to see the expected duration and uncertainty.