24/7 Staffing Calculator: How Many Employees Do I Need?

Staff needed for 24/7 cover

At 40 hours a week each. Full-time equivalents = hours to cover ÷ hours per employee. Rounding up gives the minimum; the absence column adds 15% for holidays, sickness and training (many operations use 10–25%).

How the calculation works

Hours to cover = hours open per day × days per week × people on duty. For one post covered 24/7 that is 24 × 7 × 1 = 168 hours. Divide by the hours each employee works (168 ÷ 40 = 4.2) and round up: 5 employees. Holidays, sickness, training and vacancies take people off the rota, so add a relief percentage: 4.2 × 1.15 = 4.83, still 5; at 20% it is 6.

Shift length changes how the hours are split, not the total: 168 hours is 21 eight-hour shifts or 14 twelve-hour shifts a week. With 12-hour shifts, four crews on a rotation such as the Pitman or DuPont schedule average 42 hours a week each, so overtime is built in; with 8-hour shifts, four crews on the Southern Swing also average 42 hours.

If you have fewer people

Enter the team you have. Four people covering 168 hours average 42 hours a week. On a rotation that alternates 36- and 48-hour weeks, that is 8 hours of FLSA overtime every other week, about 4 a week on average, because overtime is counted week by week. Three people would work 56 hours each. The calculator shows the average hours, the weekly overtime and any hours nobody is scheduled for.

Related pages

• Custom shift schedule generator
• Rotating shift schedules
• Overtime calculator
• 12-hour shift calculator
• Rolling absence calculator (Bradford factor)