Assumptions and method

When to be cautious

People are not interchangeable and availability is not productivity. Review bottleneck skills and timing separately.

Capacity = people × days × usable hours per day

Test a scenario

Use your own inputs

Inputs stay in your browser. Shared scenario links include your inputs.

Use the result in a decision

Keep effort, elapsed duration and skills distinct.

People are not interchangeable and availability is not productivity. Review bottleneck skills and timing separately.

Set a baseline and change one assumption to compare outcomes.

A worked example

Follow the fixed teaching example
  1. Available effort = 4 × 5 × 6 = 120 person-hours.
  2. Demand/capacity = 108/120 × 100 = 90%; spare nominal capacity = 12 person-hours.

These illustrative inputs describe a project scenario, not a published benchmark. All monetary inputs use the same currency and price basis.

People available
4
Days in period
5
Usable hours per person per day
6
Required effort (person-hours)
108
Available effort
120 person-hours
Demand / capacity
90 %
Capacity minus demand
12 person-hours

Interpret the output only within the assumptions above. Changing the inputs changes the result; it does not validate the inputs.

Source & credit

Standard estimating practice; the cited guide documents use rather than claiming invention.

GAO: Cost Estimating and Assessment Guide

This is independently written code and explanation of the underlying method. The linked publication, its diagrams and its trademarks remain its owner’s material; no permission to reuse them is implied.

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