Three-Point Estimate Calculator

Advanced three-point estimation with PERT, triangular distribution, and risk analysis

Multiple Methods

PERT, Triangular, Weighted estimates

Risk Analysis

Uncertainty and range assessment

Confidence Intervals

Statistical probability ranges

Time Estimation

Project duration forecasting

Three-Point Estimation Parameters

Simple average with equal weight

Task Estimates

days

Minimum time if everything goes perfectly

days

Most realistic estimate under normal conditions

days

Maximum time if significant issues occur

days

Minimum time if everything goes perfectly

days

Most realistic estimate under normal conditions

days

Maximum time if significant issues occur

days

Minimum time if everything goes perfectly

days

Most realistic estimate under normal conditions

days

Maximum time if significant issues occur

days

Minimum time if everything goes perfectly

days

Most realistic estimate under normal conditions

days

Maximum time if significant issues occur

days

Minimum time if everything goes perfectly

days

Most realistic estimate under normal conditions

days

Maximum time if significant issues occur

Understanding Three-Point Estimation

Estimation Methods

Triangular Distribution

Simple average of optimistic, most likely, and pessimistic estimates. Good for quick estimates when you have limited historical data and want equal weight for all scenarios.

PERT Beta Distribution

Gives 4x weight to the most likely estimate, reflecting the beta distribution's emphasis on the mode. Most commonly used in project management and recommended by PMI.

Weighted Average

Provides moderate weight (3x) to the most likely estimate. A balance between triangular and PERT methods, useful when you want to emphasize the most likely but not as strongly as PERT.

Best Practices

Estimation Guidelines

• Use historical data when available for more accurate estimates
• Involve multiple team members in the estimation process
• Document assumptions and constraints for each estimate
• Consider similar past projects as reference points

Risk Considerations

Larger ranges between optimistic and pessimistic estimates indicate higher uncertainty. Use standard deviation as a risk indicator and plan appropriate contingency buffers based on project complexity.

Continuous Improvement

Compare estimates with actual completion times to improve estimation accuracy. Track estimation performance and adjust techniques based on project outcomes and lessons learned.