Four common 12-hour rotations on one calendar
A crew is a fixed group of people who work the same days and rest together. A rotation is the repeating pattern those crews follow. Choose one of four presets: Pitman, DuPont, 4-on-4-off or 2-3-2. Then set the start date, the number of weeks to display and a start offset for each crew, which says where in the cycle that crew begins on day one.
Pitman, also called 2-2-3 or Panama, has a 14-day cycle and four crews on 12-hour shifts. Crews A and B cover days and crews C and D cover nights. Each crew works 7 of the 14 days, an average of 3.5 days a week. DuPont is a 28-day cycle with four crews, also on 12-hour shifts: 4 nights on, 3 off, 3 days on, 1 off, 3 nights on, 3 off, 4 days on, then 7 off. A DuPont crew works 14 of 28 days, again 3.5 a week.
The two-crew presets are simpler. 4-on-4-off repeats every 8 days, with 4 days worked and 4 off, so a crew averages 3.5 days a week. 2-3-2 repeats every 14 days: work 2, off 3, work 2 in the first week, then off 2, work 3, off 2 in the second. That is 7 worked days in 14, also 3.5 a week.
The calendar grid shows, day by day, who works. Download a crew as an .ics file to import into a phone or desktop calendar, or print the grid for a noticeboard. This tool lays out the pattern only. It does not check hours against any rule, so confirm your rota with whoever sets your working terms.
Worked examples
Hours a week in each rotation
Every preset averages the same number of worked days, 3.5 a week, so the weekly hours depend on the shift length. These figures are plain arithmetic on the pattern, not a statement about any working time rule.
| Rotation | Cycle (days) | Days worked in a cycle | Days a week, average | 8-hour shifts, hours a week | 12-hour shifts, hours a week |
|---|---|---|---|---|---|
| Pitman (2-2-3) | 14 | 7 | 3.5 | 28 | 42 |
| DuPont | 28 | 14 | 3.5 | 28 | 42 |
| 4-on-4-off | 8 | 4 | 3.5 | 28 | 42 |
| 2-3-2 | 14 | 7 | 3.5 | 28 | 42 |
Days a week = days worked in a cycle divided by the cycle length, times 7. Hours a week = days a week times shift length. The presets in the tool are 12-hour rotations; the 8-hour column is for comparison.
Questions about this tool
Why do the crews have offsets?
The offset moves a crew forward in the cycle so crews do not all start at the same point. Changing an offset shifts that crew and leaves the others where they are.
Is a 2-2-3 rotation the same as Pitman?
Yes. Pitman, 2-2-3 and Panama are three names for the same 14-day pattern with four crews. The preset is labelled with all of them so you can find it.
How many crews does each preset use?
Pitman and DuPont use four crews. 4-on-4-off and 2-3-2 use two crews that cover for each other.
Can I add the schedule to my phone calendar?
Yes. Download the .ics file for your crew and open it in your calendar app. Each crew has its own file, so you only import your own days.
Does the grid check legal limits on hours?
No. It only repeats the pattern you chose. Whether a pattern suits your workplace is a question for your employer or local rules.