24/72 Shift Calculator

A 24/72 is a career-fire rotation where you work a single 24-hour shift, then you are off for 72 hours before the cycle repeats. The cycle is four calendar days long, so it needs four platoons, usually labeled A, B, C, and D shift. That is the key difference from a 24/48, which fits three platoons into a three-day cycle; the extra day off is what forces the fourth platoon.

Because the cycle is four days and each firefighter works one of those four days, the pattern is perfectly even. Enter one real on-duty date in the calculator above and it phases the whole rotation to your actual platoon, then lists your on-duty days for the next 24 months so the dates match the board at your station rather than a generic template.

Over one four-day cycle you work a single 24-hour shift, which averages to 6 hours a day, or 42.0 hours across a 7-day week (24 divided by 4, times 7). That is the lowest average of any common fire rotation, well below the roughly 56 hours a straight 24/48 or 48/96 runs.

Annualized, a straight 24/72 comes to about 91 shifts a year and roughly 2,190 hours. Fewer hours on the clock is the entire appeal: more consecutive days off for recovery, second jobs, family, or long commutes, without the built-in overtime that the three-platoon schedules carry.

Fire departments do not measure overtime on a 40-hour week. Under FLSA Section 7(k) they declare a work period of up to 28 days, and for fire protection employees a 28-day period caps straight time at 212 hours. A 24/72 runs only about 168 hours in that same 28 days, which sits comfortably under the cap, so the recurring schedule itself generates no scheduled overtime.

That does not mean a 24/72 firefighter never sees overtime; it means none of it is baked into the rotation. Overtime here comes from call-backs, held-over incidents, mandatory staffing, or shifts you pick up in trade, and it stacks on top of the roughly 168-hour base. If you want to model a specific work period against the fire thresholds, the FLSA 7(k) overtime calculator breaks it down.

The 42-hour week is not free. Because a 24/72 spreads the same daily coverage across four platoons instead of three, it needs roughly 33 percent more personnel to staff the same number of seats. Every apparatus that runs 24/7 needs a fourth crew, which is a real line item in a department budget.

That headcount cost is why smaller and volunteer departments rarely run a straight 24/72: they simply do not have the bodies to field a fourth platoon on every unit. It tends to show up in larger, well-funded career departments that can afford the extra staffing in exchange for a lighter, lower-overtime schedule.

You will find 24/72 rotations mostly in larger career fire departments and some hospital-based or third-service EMS agencies that have both the staffing depth and the budget for a fourth platoon. It is popular where recruitment and retention matter, because the extra recovery days and the near-zero built-in overtime make the schedule easy to sell to crews.

If your department is weighing a move to 24/72, the calculator above lets you project the exact days for each of the four platoons and confirm the hours land near 42 a week before anyone commits. You can download the result as an .ics calendar, share it with a link, or print it for a shift meeting.