Project Calendar

A project calendar defines which days and hours are available for scheduling work. It is the foundation that converts task duration into real dates — specifying that a 5-day task runs Monday through Friday, that no work occurs on weekends, and that specific public holidays are nonworking. Without a calendar, a scheduling engine cannot compute start or finish dates from a duration estimate.

What a Project Calendar Controls

A project calendar specifies:

• Working days of the week — which days (e.g., Monday through Friday) count as schedulable time
• Daily working hours — the start and end of the working day (e.g., 8 AM to 5 PM)
• Nonworking dates — specific holidays, company shutdowns, or blackout periods
• Shift patterns — for resources on rotating or extended schedules, multiple working windows within a day

When the scheduling engine computes a task's finish date, it walks forward from the start date counting only working hours until the task's duration is fully consumed. Weekends and holidays are skipped automatically.

Resource Calendars vs. Project Calendars

Most scheduling tools distinguish between a project calendar — the default working schedule for all tasks — and resource calendars, which define the individual schedule of each person or machine. A resource calendar can override the project calendar. A part-time employee working Tuesday and Thursday has a different resource calendar than a full-time colleague; a machine running a single eight-hour shift differs from one running 24/7.

When a task is assigned to a resource, the resource's calendar governs the finish date calculation, not the project default. This means two identical tasks with the same duration but different resource assignments can have very different finish dates depending on each resource's available hours.

How Nonworking Time Affects the Schedule

Adding a public holiday between a task's start and planned finish pushes the finish date out by one working day. If that task is on the critical path, the project end date shifts by the same amount. A schedule built without accurate holiday data understates project duration by the number of unaccounted nonworking days — which is why calendar accuracy matters as much as duration estimation.

Project Calendars in Maverick

Maverick computes finish dates from each resource's individual working schedule. Assigning a task to a resource with a different schedule automatically recalculates the finish date. For a detailed look at how resource schedules interact with task date computation, see the guide: Resource Schedules and Working Hours.

Related Terms

Task Duration  ·  Task Dependency  ·  Resource Leveling  ·  Critical Path  ·  Gantt Chart