The DuPont schedule, explained

The DuPont schedule is a four-week rotation covering 24-hour operations with four crews. It is best known for one feature: a full week off in every cycle.

The cycle

Over 28 days, one crew works:

Week	Pattern
1	4 nights on, 3 off
2	3 days on, 1 off, 3 nights on
3	3 off, 4 days on
4	7 days off

That averages 42 hours a week, in 12-hour shifts, with the fourth week entirely free.

What is genuinely good about it

The seven off is real. Not a long weekend — a full week, every month, without using leave. Enough for a proper holiday, and the single biggest reason crews defend this pattern.

It is completely predictable. Four weeks is a whole number of weeks, so unlike 4-on-4-off or Kelly, the pattern does line up with the calendar. Your weeks repeat on the same weekdays every cycle. That makes it far more legible from outside than its complexity suggests.

No overtime needed. Four crews, 42 hours average, full coverage.

What is hard about it

It rotates days and nights inside a single week. Week 2 is the problem: three day shifts, one day off, then three night shifts. That single day is expected to absorb a complete inversion of your body clock, and it does not. Most people describe week 2 as the worst part of the cycle by a distance.

Twelve-hour shifts, four in a row, on nights. Week 1 opens with four consecutive night shifts. Cumulative fatigue across four 12-hour nights is significant, and the research on error rates in the later hours of long night shifts is not reassuring.

The seven-off is partly recovery. The famous week off follows four day shifts, which is the gentler ending — but across a full cycle sleep debt accumulates, and a meaningful part of week 4 goes on repaying it rather than on holiday.

What it does at home

Better than most rotations, with one caveat.

The four-week cycle means family can learn it. “Week 4 he’s off” is retainable in a way “he’s on a nine-day cycle” is not. Anniversaries, school holidays and family events can be planned against the cycle months ahead — genuinely useful, and unusual among rotating patterns.

The caveat is the same one every rotating pattern has: “off” and “available” are not the same. The three days off in week 1 follow four nights, so the first is sleep. The single day off in week 2 is a turnaround day, not a day out. A family calendar that marks all of these as free will produce disappointment on a predictable schedule.

The fix is boring and effective: put the recovery in as an event. If sleep after a night block is visible, nobody plans over it, and nobody has to be told again.

If you are moving onto it

From people who have worked it:

• Protect the first sleep after the four nights. The rest of the block depends on it.
• Treat week 2’s single day off as a turnaround, not a day off. Plan nothing.
• Use week 4 properly. It is the thing that makes the pattern worth working; people who spend it on chores tend to burn out on the rotation.
• Anchor recurring commitments to the cycle, not to weekdays. Anything weekly will be missed for chunks of the month.

Getting it into a calendar

DuPont is a four-week repeating pattern, so it can be expressed in tools that only understand weekly recurrence — you just need four separate recurring events on a 28-day interval, which is fiddly but possible.

It is easier in anything that takes a rotation directly: set the pattern once, and the days generate forward. Freeish does this, as do most dedicated shift calendar apps. The thing to check either way is that the calendar distinguishes a night shift from a day shift, because on this pattern that distinction is most of the information.