Why rotating shifts don’t fit a weekly calendar
Calendars and phone alarms repeat by the week. Rotations don’t. Four days on and four off is an 8-day cycle, so each stretch starts one weekday later than the last, and the same weekdays only come back after 8 weeks. Alarms set for Monday to Thursday are wrong by the next week, and a schedule copied into a calendar by hand drifts the first time a day is missed.
The common rotations
| Rotation | Repeats every | Shifts per cycle | Average a week | Longest stretch on / off |
|---|---|---|---|---|
| 4 on, 4 off | 8 days | 4 | 42 h | 4 on / 4 off |
| 2 days, 2 nights, 4 off | 8 days | 4 | 42 h | 4 on / 4 off |
| 2-2-3 (Pitman, Panama) | 14 days | 7 | 42 h | 3 on / 3 off |
| DuPont | 28 days | 14 | 42 h | 4 on / 7 off |
| 24/48 | 3 days | 1 | 56 h | 1 on / 2 off |
| 48/96 | 6 days | 2 | 56 h | 2 on / 4 off |
Hours assume 12-hour day and night shifts, and 24-hour shifts for 24/48 and 48/96.
- 4 on, 4 off
- Four shifts, then four days off, in an 8-day cycle. With 12-hour shifts that’s 48 hours every 8 days, an average of 42 a week; any single week holds 36 or 48. Day or night shifts; switch them in the maker.
- 2 days, 2 nights, 4 off
- The same 8-day cycle, with two day shifts followed by two night shifts. The first day off goes mostly to sleep after the last night.
- 2-2-3 (Pitman, Panama)
- Work 2, off 2, work 3, off 2, work 2, off 3: seven shifts in 14 days, so the same weekdays come back every other week. Employers use the two names differently, and some move crews between days and nights every few weeks. If yours does, start from 2-2-3 and edit it under Custom.
- DuPont
- 4 nights, 3 off, 3 days, 1 off, 3 nights, 3 off, 4 days, then 7 off: fourteen 12-hour shifts in 28 days, and a week off once a cycle.
- 24/48
- One 24-hour shift, then two days off, common in fire and EMS departments. It repeats every third day, so it never stays on the same weekday, and averages 56 hours a week.
- 48/96
- Two 24-hour shifts back to back, then four days off: a 6-day cycle with the same 56-hour average.
- Kelly days and local variations
- Departments add Kelly days and other exceptions in their own ways. Make the base rotation here and add the exceptions as single events, or build a different cycle under Custom.
Why your iPhone alarm can’t follow a rotation
- The Clock app repeats alarms on chosen weekdays only. A rotation that moves one weekday a week needs its alarms changed every week.
- Reminders can repeat every few days (Repeat → Custom → every 8 days), but a reminder is a notification: it doesn’t ring like an alarm, and the Ring/Silent switch and Focus can mute it.
- Calendar alerts work the same way. The file above can add an alert before each shift, and it arrives on time, but as a notification.
- Shortcuts can do it with a daily automation that works out whether tomorrow is a work day and turns an alarm on or off. It takes some building, and it needs changing when your rotation does.
How to add your shifts to your calendar
The file works with every major calendar app. Import it once and the rotation fills in for as long as you chose.
- 1
Find your rotation and a day you’re sure of
Check your rota or contract for the pattern, and pick one date where you know exactly what you’re working, such as the first shift of your next stretch.
- 2
Set it up
Pick the rotation, set your shift times, enter the date and tap which day of the rotation it is. Crews on the same rotation differ only in that day.
- 3
Check the preview
Flip to a month you already know and compare. If the shifts look shifted, the date or the day of the rotation is off.
- 4
Download the calendar file, or print it
The .ics file holds one timed event per shift in the cycle, each repeating every cycle until the end date you picked. Days off stay empty. For paper, Print or save as PDF puts each year on one page.
- 5
Import it
iPhone or iPad: open the file and tap Add All. Mac: double-click it, or File → Import in Calendar. Google Calendar: on a computer, Settings → Import & export → Import, then pick the calendar. Outlook: Add calendar → Upload from file.
What a calendar file can’t do
- It holds the regular rotation only. Overtime, swaps, training days and holidays are yours to add as single events, and to delete the shifts they replace.
- It doesn’t update itself. If your employer changes the rota, make a new file and delete the old events, or the two overlap.
- Its alerts are notifications, not alarms, and Google Calendar may replace them with your default notifications when it imports the file.
- Shift times are local clock times: a 7 am shift stays at 7 am through daylight saving changes and if you travel.
- Nothing you type is uploaded. The file is built in your browser and saved straight to your device; we only count which rotation was downloaded.
Never sleep through a shift
The calendar file shows when you work. Smart Calendars adds what a file can’t: an alarm before every shift that follows your rotation instead of the weekday, and rings until you stop it, with three sounds and Snooze, on iPhone and iPad with iOS 26 or later. Describe your rotation in a sentence, the way you’d explain it to a coworker, and ask for the alarms; the generator above writes that sentence for your exact schedule.
Overtime, swaps and a new rota work the same way: type the change, or photograph the printed rota, and check each event before it’s saved.
Got your rota as a file or a photo?
Questions
- How many hours is a 4 on 4 off schedule?
- With 12-hour shifts, 48 hours every 8 days, an average of 42 a week. Because the 8-day cycle doesn’t line up with the week, any single week holds 36 or 48 hours.
- How does a 2-2-3 schedule work?
- You work 2 days, have 2 off, work 3, have 2 off, work 2 and have 3 off, then it repeats. That’s 7 shifts in 14 days, 84 hours with 12-hour shifts, or 42 a week on average. How those hours split between two weeks depends on the day your pay week starts.
- What is the DuPont schedule?
- A 28-day rotation of 12-hour shifts: 4 nights, 3 days off, 3 days, 1 day off, 3 nights, 3 days off, 4 days, then 7 days off. That’s 14 shifts, an average of 42 hours a week, and a full week off once a cycle.
- How do I set an iPhone alarm for every other day, or every 4 days?
- Not in the Clock app: its alarms repeat on chosen weekdays only. Reminders can repeat every few days, but they arrive as notifications. Smart Calendars puts an alarm on each shift in your calendar, so it follows the rotation instead of the weekday (iOS and iPadOS 26 or later).
- My crew is B shift. How do I get my days?
- Crews work the same rotation at different points in the cycle. Pick a date you know and tap which day of the rotation it is for you; that sets your crew.
- My rotation isn’t listed. Can I still use this?
- Yes. Choose Custom and build the cycle day by day: day shift, night shift, 24-hour shift or off, up to 42 days long. Starting from the closest listed rotation is usually quickest.
- Does it work with Google Calendar and Outlook?
- Yes. The .ics file imports into Apple Calendar, Google Calendar and Outlook. Each shift is one repeating event, so the rotation continues until the end date you picked.