The simplest rotating schedules are the ones named by their days: 4 on 4 off, 4 on 2 off, 2 on 2 off. Each is a crew working a fixed run of days and then a fixed run off, repeating without regard to the calendar, so that the working days drift through the week and every crew gets every day of the week off in turn. They are common in security, care homes, distribution centers and 24-hour retail, and they are easy to explain and hard to argue with. This page sets out what each pattern does to a person's hours and weekends, why a 4 on 2 off schedule needs a different headcount from a 4 on 4 off schedule, and how the rotating schedule generator on this site lays any of them out from two numbers.
4 on 4 off: half the days, on 12-hour shifts
Four days on, four off, in an eight-day cycle. On 12-hour shifts that is 48 hours in the four working days and an average of 42 a week over the year, the same average as a 2-2-3 with a different shape: four 12-hour days in a row instead of two or three, and four days off in a row instead of two or three. Because the cycle is eight days and the week is seven, the working days move back one day each cycle, so a crew works every day of the week over eight cycles and gets every weekend off over the same span. Covering the clock takes four crews, two on days and two on nights, exactly as the 2-2-3 does.
4 on 2 off and 2 on 2 off: two-thirds and half
Four on, two off is a six-day cycle in which a crew works two-thirds of its days: on eight-hour shifts that is 37.3 hours a week on average and on 12-hour shifts 56, which is why a 4 on 2 off schedule is an eight-hour pattern in practice, common in retail and care where three eight-hour shifts cover a day and three crews are on at any time. Two on, two off is a four-day cycle at half the days: on 12-hour shifts it averages 42 hours a week like the 4 on 4 off, with shorter runs both ways, and it is the pattern of choice where a two-day stretch of nights is all a crew will tolerate. A 2 on 2 off work schedule and a 4 on 4 off need the same four crews to cover the clock; a 4 on 2 off on eight-hour shifts needs four and a half, which in practice means five crews or part-timers.
Laying any of them out
Every one of these patterns reduces to days on in a cycle and cycle length, plus the shift length: 4 in 8, 4 in 6, 2 in 4. The rotating schedule generator on this site takes those two numbers and the shift length and returns the average hours a week, the hours over forty, the crews and the people needed to cover the clock, and the cost of a cycle, which is how a manager finds out that a 4 on 2 off schedule generator producing 56-hour weeks on 12-hour shifts is producing a problem. The federal Fair Labor Standards Act counts overtime on hours over forty in each workweek, and a pattern whose cycle is not seven days puts a different number of shifts in each week, so the published schedule and the workweek definition have to be read together.
Questions people ask about 4 on 4 off schedule
How many hours a week is 4 on 4 off?
An average of 42 on 12-hour shifts, made of alternating weeks of three and four shifts. On eight-hour shifts it averages 28, which is why it is a 12-hour pattern in practice.
How many crews does a 4 on 2 off schedule need?
Three crews cover one shift a day; on eight-hour shifts covering the clock takes four and a half crews, which means five crews or part-timers filling the half.
Do you always get weekends off on a 2 on 2 off?
You get every weekend off in turn: the four-day cycle drifts through the seven-day week, so every crew sees every combination of days over a run of cycles.