Worked example
A four-on/four-off pattern does not simply mean half the year at work once leave and 12-hour shifts are considered.
Frequently asked questions
Can I use this for 2 days, 2 nights, 4 off?
Yes, if all four working shifts are the same duration. Enter four work shifts and four rest days.
Does this account for leap years or roster quirks?
No. It is an annualised estimate based on a 365-day repeating cycle.
Annualise a repeating shift pattern
Repeating rosters such as four-on/four-off do not map neatly onto calendar weeks. This tool converts the work/rest cycle into an estimated number of annual shifts and hours, then deducts annual leave shifts entered by the user.
For mixed shift lengths, such as a rotation containing both 8-hour and 12-hour duties, a single average can hide important detail. Run separate calculations or calculate a representative average only if that is accurate enough for your planning purpose.
Useful checks for roster comparisons
- confirm whether paid breaks are included in shift length;
- check how annual leave is deducted from rostered shifts;
- consider training, standby or reserve duties separately;
- remember that real rosters can vary around holidays and leap years.
The result is an annualised estimate based on a 365-day cycle. It is useful for comparing patterns, but your employer's published roster remains the source of truth for contracted hours.