Time Calculator
Calculate exact elapsed time between two timestamps, deduct lunch breaks for net work hours, find your clock-out time, sum up multiple time intervals, and convert between decimal hours and minutes.
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 pomodoro sprints, revision sessions, or focus blocks across multiple tasks.
- 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 the time between two times?▾
In the "Between Times" mode, enter your Start Time and End Time. The calculator computes the exact elapsed duration in hours and minutes. If the end time is earlier than the start time (such as 10:00 PM to 6:00 AM), the calculator automatically detects that the shift crossed midnight into the next day.
How do I calculate my work hours with a lunch break?▾
Enter your shift start time and end time, check "Deduct a break", and enter your unpaid break length (such as 30 or 45 minutes). The calculator will subtract your break from the total elapsed time to display your exact net hours worked.
How do I find what time I should clock out?▾
Switch to the "Clock Out" mode. Enter your shift start time (e.g., 9:00 AM), required work duration (e.g., 8 hours), and any unpaid lunch break (e.g., 30 minutes). The tool instantly calculates your exact target clock-out time (5:30 PM).
How are overnight shifts crossing midnight calculated?▾
When your end time is earlier than your start time (for instance, starting at 10:30 PM and ending at 6:30 AM), our calculator automatically recognizes that midnight has passed and adds 24 hours to the end time, displaying an "Overnight · +1 day" indicator.
How do I add or subtract multiple time durations?▾
Use the "Add / Subtract" mode. Enter your starting duration, choose "+" or "−" on subsequent rows, and click "+ Add Another Time" to add as many duration rows as needed (up to 10 rows). This is ideal for adding daily work logs or cumulative project hours.
How do I convert decimal hours to hours and minutes?▾
Use the "Decimal Hours" mode. Enter your decimal number (e.g., 7.75 hours) to see it converted into 7 hours and 45 minutes (0.75 × 60 = 45 mins). You can also enter hours and minutes to convert into payroll decimal hours.
Can I use 24-hour military time?▾
Yes. Use the format toggle at the top of the calculator to switch between 12-Hour (AM/PM) and 24-Hour (Military) format. Your preference is remembered automatically on your device.
Are my work hours and calculation data private?▾
Yes. Calculations run locally in your browser. Your calculation values are not sent to our server, stored in any database, or added to page URLs.
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