Time Calculator
Calculate exact elapsed time between two timestamps, add or subtract hours and minutes, and compute net work shift totals with unpaid breaks. Includes decimal hour conversions for payroll.
8.00 hours · 480 minutes (8h 30m total − 30m break)
How to Calculate Time & Work Hours
Calculating duration between two timestamps involves converting both times into total elapsed minutes from midnight, subtracting the start time from the end time, and formatting the result into hours and remaining minutes.
1. Standard Same-Day Spans
Subtract the earlier start time from the later end time. For example, 9:00 AM to 5:30 PM equals 8 hours and 30 minutes.
2. Overnight Shifts (Crossing Midnight)
When the end time is on the following morning (e.g., 10:00 PM to 6:00 AM), add 24 hours (1,440 minutes) to the end time before subtracting.
Common Use Cases for Time Calculations
- Workplace Timesheets: Determine exact billable hours worked after deducting unpaid lunch and rest breaks.
- Clock-Out Planning: Know precisely what time to leave the office to meet your mandatory 8-hour shift requirement.
- Project & Study Tracking: Add up individual focus sprints, revision sessions, or client tasks across multiple intervals.
- Payroll Preparation: Convert fractional decimal hours (e.g., 37.75 hours) to standard hours and minutes for employee records.
Frequently Asked Questions
How do I calculate work hours with an unpaid lunch break?▾
Enter your shift start time and end time in the Time Between tool, then enter your break duration (e.g., 30 or 60 minutes) in the "Break Deductions" field. The calculator automatically subtracts break time from gross hours to give your net billable time.
How are overnight shifts crossing midnight handled?▾
Our calculator automatically detects when the end time occurs numerically earlier than the start time (e.g., 10:00 PM to 6:30 AM) and treats the end time as the following calendar day, adding 24 hours to yield the correct 8 hours and 30 minutes duration.
How do decimal hours convert to minutes?▾
To convert decimal hours to minutes, multiply the fractional part by 60. For example, 7.75 hours equals 7 hours plus (0.75 × 60 = 45 minutes), totaling 7 hours and 45 minutes.
Can I add or subtract multiple time durations together?▾
Yes. Switch to the "Add / Subtract" tab to chain multiple durations together, calculate future completion times, or subtract elapsed intervals from a budget.
Is my timesheet and schedule information private?▾
Yes. All time math executes completely client-side in your browser. None of your work hours, timestamps, or calculations are ever transmitted to any remote server.
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