Shift Hours (Overnight) Calculator

Easily calculate working hours for shifts that start on one day and end on the next (overnight shifts).

Enter your shift start and end times. If your shift crosses midnight (e.g., starts at 10:00 PM and ends at 6:00 AM), our calculator automatically detects the day change and calculates the correct duration.

Note for Overnight Shifts: If your End Time is earlier than your Start Time (e.g. Start 22:00, End 06:00), the calculator assumes the shift ends the following day.

Calculating Overnight & Night Shift Hours

Calculating hours for shifts that cross midnight can be tricky with standard calculators that assume a single-day schedule. A shift from 10:00 PM to 6:00 AM might mathematically look like negative hours if not handled correctly.

Who is this tool for?

This tool is essential for:

  • Night Shift Workers: Nurses, security guards, factory workers, and logistics staff.
  • Rotating Shift Schedules: Employees whose hours change weekly.
  • Payroll Managers: Verifying hours for employees working irregular schedules.

Logic Used

The calculator checks your AM/PM selection. If your Start Time is PM and your End Time is AM (or if End Time is numerically smaller than Start Time in 24h format), it logically adds 24 hours to the end time to determine the correct duration.

Example Calculation

Start: 10:00 PM, End: 6:00 AM

Math: (6 + 24) - 22 = 8 hours

Frequently Asked Questions

How do I calculate hours for an overnight shift?

If you start work on one day (e.g., 10 PM) and finish on the next (e.g., 6 AM), you must account for the midnight crossover. Our calculator assumes that if the End Time is earlier than the Start Time, the shift ended the next day, and calculates the total duration (8 hours) automatically.

Does the 24-hour clock make it easier?

Yes. Using military time (00:00 - 23:59) is often less confusing for overnight shifts, but this calculator works perfectly with standard AM/PM times too.

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Did you know?

USA federal law requires overtime pay at 1.5x for hours worked over 40 in a workweek.