3x12 shift calendar

How to use your calendar

1. Open Edit settings on a phone or tablet, then choose fixed weekdays or your own rotating cycle.
2. For fixed shifts, select exactly three weekdays. For rotating shifts, enter the full employer cycle using D for day, N for night and O for off.
3. Choose a start date and the year to show. Earlier dates stay blank, even if they fall on a selected weekday.
4. Enter the local shift start times. Each shift finishes 12 scheduled hours later, including overnight shifts.
5. Check known dates and the monthly hours against your workplace rota. Save, share a settings link, print or download the calendar file.

How it works

A fixed 3x12 schedule places three 12-hour shifts on the same three weekdays every week, giving 36 scheduled hours in a complete week. The start date limits when the calendar begins; it does not change which weekdays are worked.

Rotating schedules vary by employer. Duke Health provides an example of a three-shift week that rotates between days and nights, but does not define one universal repeating cycle. Enter your employer's complete sequence rather than assuming a preset fits your workplace.

The rotating cycle repeats continuously from its first code on the start date. Its average shifts per week are seven multiplied by the number of D and N codes, divided by the total cycle length. A warning appears when this average differs from three. Individual weeks and months can still have different counts.

Monthly hours equal the shifts whose start dates fall in that month multiplied by 12. A night shift beginning on the final date of a month belongs entirely to that month for these totals. The same rule applies at year end. These are nominal scheduled hours, before unpaid breaks, leave, swaps or overtime.

Calendar-day arithmetic keeps weekdays and cycles consistent through leap days and daylight saving changes. Downloads use local floating start and end times so the clock times remain the ones you entered. An overnight shift ends on the next date. Repeated same-code runs use one calendar event with daily occurrences; off dates are excluded. Check how your calendar app handles its time zone and reminders.

Settings are kept on your device when you save. Sharing puts the settings in the link fragment for the recipient to open. Delete my data removes the saved settings, clears the share fragment and resets the form.

Worked example

Choose Monday, Wednesday and Friday, start on Friday, 1 January 2027, and show 2027:

• January shifts start on 1, 4, 6, 8, 11, 13, 15, 18, 20, 22, 25, 27 and 29 January.
• That is 13 shifts and 156 scheduled hours in January: 13 multiplied by 12.
• The default 07:00 start finishes at 19:00. Changing a start to 19:00 makes the end 07:00 the next day, while keeping 12 nominal hours per shift.

Common questions

Related tools

• Shift pattern calendar generator
• Shift hours calculator
• Who is on shift finder