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PERT, in plain English.

The method the US Navy developed in the 1950s to schedule work nobody had done before, built into a tool you can learn in an afternoon.

Three estimates. One honest number.

For each task, tell Pertify the best case, the most likely case and the worst case. It weighs them into an expected time, leaning toward the likely case without ignoring the risk.

Expected time = (best + 4 × likely + worst) ÷ 6

Sure of a task? Enter one number and Pertify uses it as is.

Table of interior tasks with optimistic, realistic and pessimistic estimates and the expected time
[Example plan caption pending]

Try it. Drag the estimates.

[Interactive demo pending spec]

  • Best case
  • Most likely
  • Worst case
Expected time
—
Project finish
—
On the critical path? (Yes / No)
—
Slack
—

Push the worst case out and watch the finish date move.

  1. Find the critical path.

    Link tasks together and Pertify shows the chain that sets your finish date. If an edit changes that chain, you'll be asked to confirm.

  2. Know your slack.

    Every other task shows how many days it can slip before it matters.

  3. Set a baseline.

    Save the plan you agreed to, then compare every change against it.

  4. Track reality.

    Start and finish tasks with one tap. Pertify records actual dates and shows plan versus actual on the Timeline.

Close-up of the critical path running from foundation into framing, with the crew on each task
[Example plan caption pending]
Baselines panel with contingency and management reserve and three saved baselines
[Example plan caption pending]

See it on your own project.

Join the beta