Overnight Shift Calculator: Hours Across Midnight

Calculate exact hours for 3rd shift, graveyard, and overnight schedules without 'negative hour' errors.

Top Tool for 3rd Shift: This calculator is optimized to handle 12-hour and 8-hour overnight shifts that cross the midnight hour.

Common Overnight Shifts

10 PM - 6 AM
8.0 Hours
7 PM - 7 AM
12.0 Hours
11 PM - 7 AM
8.0 Hours

Overnight Calculation Logic

// How we solve the midnight crossover:

IF (End_Time < Start_Time) {

Total_Hours = (End_Time + 24) - Start_Time;

} ELSE {

Total_Hours = End_Time - Start_Time;

}

Our overnight calculator detects if your shift ends the next day and adjusts automatically.

Why Use an Overnight Shift Calculator?

Calculating a night shift (3rd shift) is notoriously difficult on standard calculators. When a shift starts at 11:00 PM and ends at 7:00 AM, a basic subtraction results in a negative number. This tool is programmed with crossover logic to provide 100% accurate durations for night-time workers.

3rd Shift & Graveyard

Perfect for logistics, security, and warehouse workers who consistently cross the 12:00 AM threshold.

12-Hour Nursing Shifts

Specifically designed for healthcare professionals working 7 PM to 7 AM rotations.

How to Calculate Night Shift Hours

  • 1Input your Start Time (e.g., 22:00 or 10:00 PM).
  • 2Input your End Time on the following morning (e.g., 06:00 or 6:00 AM).
  • 3Enter any unpaid break time in minutes (e.g., 30).
  • 4The calculator provides your Net Paid Hours in both decimal and HH:MM format.

Common Questions

How do you calculate hours for a shift that crosses midnight?

To calculate overnight hours, if the end time is on the next day, add 24 to the end time before subtracting the start time. For example, 10 PM (22:00) to 6 AM (06:00) becomes (06:00 + 24) - 22:00 = 8 hours.

Does this overnight calculator support 24-hour military time?

Yes. You can enter times in either 12-hour (AM/PM) or 24-hour (military) format. It is specifically designed for 3rd shift workers who use 24-hour logs.

How are breaks deducted from a night shift?

Enter your total unpaid break time in minutes. The calculator converts this to decimal format and subtracts it from the total elapsed time, ensuring you only see paid working hours.