Overnight Shift Calculator
Calculate hours for shifts that cross midnight (third shifts, graveyard shifts, and night duty). Automatically adjusts for 24-hour midnight crossing with break deductions.
Quick Answer: Overnight Shift Calculation Formula
When a work shift crosses midnight, calculate hours before midnight, add hours after midnight, and subtract unpaid breaks:
• Standard Example: 10:00 PM (22:00) to 06:30 AM (06:30) with 30m break = 2h + 6.5h − 0.5h = 8.00 Net Hours.
Total Work Hours
35:00
35.00 decimal hrs
Regular Hours
35:00
35.00 decimal hrs
Overtime Hours
0:00
0.00 decimal hrs
Days Worked
5 days
Avg: 7:00/day (7.00h)
Weekly overtime threshold: 40 hours/week (Multiplier: 1.5x). Based on standard US FLSA rules; specific state or contract rules (e.g. CA daily overtime) may apply.
Overnight Worked Example
Scenario: 10:00 PM to 6:00 AM Hospital or Warehouse Shift
- • Shift Start: 22:00 (10:00 PM)
- • Shift End: 06:00 (6:00 AM the following morning)
- • Unpaid Meal Break: 30 minutes (0.5 hours)
- • Elapsed Shift Time: (24:00 − 22:00) + 06:00 = 2h + 6h = 8.0 hours
- • Net Paid Hours: 8.0 − 0.5 = 7.50 Decimal Hours (7 hours 30 minutes)
Federal Payroll Rules for Overnight Shifts
Under federal guidelines (29 CFR Part 778), managing overnight shifts requires consistent workweek accounting:
- Shift Differentials Included in Regular Rate: Any extra pay or differential awarded for working night shifts must be added to the regular rate before computing overtime.
- Single Workweek Definition: Shifts that cross midnight cannot be arbitrarily divided across two workweeks to evade 40-hour overtime thresholds.
Frequently Asked Questions
How do you calculate work hours for a shift that crosses midnight?
Calculate the hours worked before midnight (24:00 minus your start time), add the hours worked after midnight (your end time), and subtract any unpaid break minutes. For example: starting at 22:00 (10:00 PM) and finishing at 06:30 (6:30 AM) with a 30-minute break equals 2 hours + 6.5 hours − 0.5 hours = 8.00 hours worked.
Does Shiftfy automatically detect overnight shifts?
Yes. Whenever your shift end time is numerically earlier than your start time (such as starting at 23:00 and ending at 07:00), the calculator automatically detects that the shift transitions across midnight and computes the exact duration.
How does an overnight shift allocate to payroll workweeks?
Under FLSA rules (29 CFR § 778.105), an employer establishes a fixed workweek (e.g. Sunday midnight to Saturday 11:59 PM). Shifts crossing midnight are typically assigned to the workday on which the majority of hours occurred or the day the shift began, according to company payroll policy.
What is a night shift differential and how does it apply?
A shift differential is additional compensation (often an extra $1 to $4 per hour or a percentage premium) paid to employees working night or graveyard shifts. Under federal overtime rules, night shift differentials must be included in the employee's regular rate when calculating overtime.
Can I enter overnight shifts using 12-hour AM/PM time?
Yes. You can use standard 12-hour AM/PM format (e.g. 10:00 PM to 6:00 AM) or switch to 24-hour military notation (22:00 to 06:00) using the calculator format toggle.
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