How does the PERT formula work?

PERT Expected Duration = (Optimistic + 4 × Most Likely + Pessimistic) ÷ 6.

PERT helps you forecast realistic timelines by accounting for uncertainty and risk in task duration estimates.

PERT Estimate Calculator (Three-Point Estimate)

Use this PERT Calculator to generate a realistic duration estimate from optimistic, most likely, and pessimistic task durations.

PERT Calculator

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

Formula

Expected Duration (PERT) = (O + 4M + P) ÷ 6

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