Calculator

Project Duration Calculator

Turn task counts, average effort, parallel work lanes and contingency into a simple elapsed-time estimate.

Project Duration Calculator

Use only when work can genuinely be split across the selected parallel lanes.

Work content first

Task count multiplied by average effort estimates total work content. Shared setup is added once.

Parallel work assumption

Dividing by parallel lanes assumes those lanes can work independently. Shared bottlenecks, dependencies and coordination can make elapsed time longer.

Buffer

The buffer is applied after the idealized division of work. It is a planning allowance, not a substitute for modelling known tasks or waits.

ImportantResults are planning estimates produced from the values you enter. Verify any deadline, safety requirement, product wait, legal period, service life or professional requirement with the source that governs your situation.

Improve the estimate

After the task is complete, compare actual active time, waiting time and elapsed time with your inputs. Updating your own rates is one of the simplest ways to make future estimates more useful.