The shift schedule generator above lays out a rotating roster across every crew and then tells you what it costs. It prints the full cycle so you can see which crew is on days, on nights or off on any given date, and it works out hours, overtime and pay per crew from the pattern rather than from an assumed weekly average.
Arb Digital builds free calculators that surface the number people miss. Here that number is overtime. All three continuous patterns below average exactly 42 hours a week, but they generate wildly different overtime because overtime is assessed week by week, not on the average. That single fact changes the cost of a roster by tens of thousands over a year, and no summary that only quotes the average will show it.
What This Shift Schedule Generator Does
Four patterns are built in. The 2-2-3 or Pitman rotation runs a 14 day cycle of two on, two off, three on, two off, two on, three off, with four crews covering days and nights. The DuPont rotation runs 28 days: four nights, three off, three days, one off, three nights, three off, four days, then seven consecutive days off. The 4-on-4-off rotation runs an 8 day cycle of four shifts then four rest days. The fixed 5 on 2 off pattern is a single weekday crew on eight hour days.
For each one the tool builds the crew offsets that give continuous cover, prints the grid, and then computes hours by splitting the repeating pattern into seven day weeks. Where the cycle does not divide evenly into weeks — 4-on-4-off is 8 days long — it extends the pattern to the least common multiple with seven, which for that rotation is 56 days, so the weekly figures are true long-run averages rather than an artefact of where you started counting.
Our live work hours calculator covers the neighbouring job: it totals hours between two dates and converts decimal hours to hours and minutes. It works on hours you already have. This page produces the pattern those hours come from, which is the boundary between the two.
How to Use It
- Pick a rotation. Selecting one loads its conventional shift length, which you can then change.
- Set the overtime threshold to whatever rule applies to you. It is not 40 hours everywhere.
- Enter a base hourly rate and an overtime multiplier. Both are your figures; the page publishes none.
- Choose the weekday the cycle starts on if you want the roster labelled to match a real calendar.
- Read the overtime line before the average. Two rotations with identical averages can differ by a third in cost.
The Formula and How It Is Calculated
Hours per crew per cycle is simply shifts worked × shift length. Weekly hours are found by walking the repeating pattern in blocks of seven days and totalling each block, and overtime = the sum over weeks of max(0, weekly hours − threshold).
Work the 2-2-3 defaults. Each crew works 7 shifts in 14 days, so 7 × 12 = 84 hours per cycle, which is 42 hours a week on average. But the two weeks are not alike. Week one of the cycle is on, on, off, off, on, on, on — five shifts, 60 hours. Week two is off, off, on, on, off, off, off — two shifts, 24 hours. At a 40 hour threshold that is 20 overtime hours in week one and none in week two, so 10 overtime hours a week on average, against an average that never actually occurs.
Pay follows from that split. At 25 an hour with a 1.5 multiplier, week one is 40 × 25 + 20 × 37.50 = 1,750, and week two is 24 × 25 = 600. The average is 1,175 a week, which is 17.5% more than 42 hours at the flat rate would suggest.
DuPont is worse on this measure and better on rest. Its 28 day cycle gives 14 shifts, 168 hours, the same 42 hour average — but its second week contains six shifts, a 72 hour week, and the cycle produces 12 overtime hours a week on average. In exchange the crew gets seven consecutive days off at the end of every cycle, which is the reason the pattern exists.
4-on-4-off produces the same 42 hour average from a completely different distribution. Because a four-day block can never put more than five shifts into any seven day window, its long-run overtime is only 4 hours a week. Same average hours, less than half the overtime of Pitman and a third of DuPont.
Why Averages Hide the Cost
Overtime rules are almost universally assessed on a defined period — usually a week — and never on the average of several. That makes a roster's cost a function of how work is clustered, not how much of it there is. Two patterns delivering identical annual hours can differ by a third in wage cost purely because one bunches shifts into single weeks and the other spreads them.
This is why "42 hours a week" is a misleading way to describe any of these rotations. Nobody works 42 hours in a week under any of them. They work 60 and then 24, or 48 and 72 and 48 and nothing. Budgeting from the average understates the wage bill on every continuous pattern with a weekly overtime threshold.
The lever that follows is the threshold and the reference period, not the pattern. Some jurisdictions and agreements average hours over a longer reference period, which changes the answer entirely. Our overtime pay calculator handles a single week's mix of regular, overtime and double time in detail, and the payroll tax calculator takes the gross figure onward.
What Each Pattern Is Actually Trading
The 2-2-3 rotation never asks for more than three consecutive shifts and gives every other weekend off in a fixed, predictable way. Its cost is the 60 hour week, and the fact that crews alternate between days and nights, which is harder on sleep than a fixed assignment.
DuPont buys a full week off every 28 days by paying for it with a 72 hour week and a four-shift night block. Crews tend to like the long break and dislike the block. It is a common pattern in continuous process industries for that reason.
4-on-4-off has the most even distribution and the lowest overtime, and it is the only one of the three whose cycle does not align to a calendar week — days off drift through the week, so a crew never has a fixed weekend. That drift is either the pattern's best feature or its worst depending on who you ask, and it is the main practical objection to it.
The fixed 5 on 2 off pattern generates no overtime at 8 hours a day against a 40 hour threshold and provides no night or weekend cover at all. If a service needs cover outside those hours, it needs more than one crew, and the arithmetic moves to one of the rotations above.
The Rules That Sit Above Any Pattern
Maximum working hours, minimum daily and weekly rest, night work limits and how hours may be averaged are set by law and, very often, by a collective agreement that is stricter than the law. They vary enormously by jurisdiction, sector and role.
In the European Union, Directive 2003/88/EC on the organisation of working time sets a minimum daily rest period of 11 consecutive hours, a weekly rest period, a 48 hour average maximum including overtime, and specific limits on night work, with derogations available through collective agreements. In the United Kingdom, the government's guidance on the maximum weekly working hours explains that the 48 hour limit is normally averaged over 17 weeks and that individuals may opt out. Other countries set entirely different figures, and several sectors are carved out.
None of that is checked by this page. The generator arranges a pattern and prices it. It does not verify that a rotation is lawful for your workforce, that rest periods between shifts are adequate, that night work limits are met, or that a required opt-out or agreement exists. Those are questions for your legal or HR function and, where one applies, for the agreement itself.
Arb Digital designs and builds free interactive calculators that state their sources, show their arithmetic and earn links because they are genuinely useful. Browse what we have already published, or tell us what your audience keeps searching for.
Browse the Free Tools Hub Talk to Arb DigitalCommon Mistakes to Avoid
- Budgeting from the weekly average. Nobody works the average. Overtime is assessed per week, and clustering is what drives cost.
- Assuming a 40 hour threshold. The threshold and the reference period vary by jurisdiction and agreement, and both change the answer.
- Starting a short cycle at an arbitrary week. An 8 day cycle does not align to a 7 day week, so weekly figures only settle over 56 days.
- Treating the pattern as the whole roster. Holidays, sickness and training all break the rotation, and cover for them is not in these numbers.
- Confusing average hours with rest adequacy. A pattern can average 42 hours and still breach a daily rest requirement between two particular shifts.
Related Free Tools From Arb Digital
The work hours calculator totals hours between two dates, the time duration calculator handles overnight shifts and break deductions, and the overtime pay calculator breaks a single week into regular, overtime and double time. For the cost side, use the payroll tax calculator and the billable hours calculator. The add and subtract time calculator is useful for shift handover arithmetic. Everything else is on the free online tools hub.
Frequently Asked Questions
A 14 day rotation of two shifts on, two off, three on, two off, two on, three off. Four crews run it for continuous cover, two on days and two on nights. Each crew works seven 12 hour shifts per cycle, which averages 42 hours a week.
All three continuous patterns here average exactly 42 hours a week. What differs is the distribution: 2-2-3 alternates 60 hour and 24 hour weeks, DuPont runs 48, 72, 48 and 0, and 4-on-4-off spreads shifts far more evenly across a 56 day repeat.
4-on-4-off, at about 4 overtime hours a week against a 40 hour threshold. The 2-2-3 pattern produces about 10 and DuPont about 12, despite all three averaging the same 42 hours. Overtime is assessed weekly, so clustering is what drives it.
A 28 day rotation of four nights, three off, three days, one off, three nights, three off, four days and then seven consecutive days off. Four crews cover 24 hours. It trades a 72 hour week for a full week of rest every cycle.
Because an 8 day cycle does not divide into 7 day weeks. The pattern only repeats against the calendar every 56 days, which is the least common multiple, so weekly hours and overtime are averaged over that span to give a true long-run figure.
Three of them need four crews for continuous 24 hour cover: two on days and two on nights, offset so that exactly one day crew and one night crew is working every day. The fixed 5 on 2 off pattern is a single crew covering weekdays only.
No. Maximum hours, rest periods, night work limits and how hours may be averaged are set by law and by any applicable collective agreement, and they vary by jurisdiction and sector. This tool arranges and prices a pattern; it does not certify that the pattern is lawful.
No. The pay calculation uses only the base rate and overtime multiplier you enter. Shift premiums, unsocial hours payments and public holiday rates all sit outside it and would have to be added separately.
This page arranges and prices a shift pattern; it does not certify that the pattern is lawful. Maximum working hours, minimum daily and weekly rest, night work limits and permitted averaging periods are set by law and, in many workplaces, by a collective agreement that is stricter than the law, and they differ between jurisdictions and sectors. Check any roster against the rules that apply to your workforce and take advice where the answer is not obvious.
