Start calculating the costs of all your resources by professional categories with ITM Platform Man-hours, also called person-hours, are the unit of measure that is used in project management to measure the efforts needed to complete a task.ġ man hour = work completed in an hour of uninterrupted effort by an average worker.Ĭalculating man hours is the basis for being able to measure the cost per project of each type of expert and his contribution to the result.