Time Clock Calculator for Hours and Minutes
Calculate work hours, subtract breaks, total multiple shifts, check weekly overtime, and convert hours and minutes—all locally in your browser.
Start and End Time Calculator
Enter a start time, end time, and unpaid break.
Add Multiple Time Entries
Add up to 20 work periods. Dates are optional.
Weekly Time-Card Calculator
Hours and Minutes Arithmetic
Add or Subtract Time
Add result: 3 hours 45 minutes
Hours and Minutes Conversion
510 minutes · 8.50 decimal hours
Minutes to Hours and Minutes
8 hours 30 minutes
Decimal Hours to Hours and Minutes
7 hours 45 minutes
Time Results
Your time entries are calculated locally in your browser. No time-card information is uploaded or stored.
How to Use the Time Clock Calculator
Choose a time format, enter start and end times, then add any unpaid break. The time clock calculator updates gross time, net work time, minutes, and decimal hours. Use the expandable sections for multiple shifts, weekly totals, and conversions.
How Time Clock Hours Are Calculated
The calculator converts each time to minutes after midnight, finds the elapsed duration, and subtracts unpaid breaks. Working in whole minutes avoids floating-point errors.
Net Work Time = End Time − Start Time − Break Time
How to Calculate Hours and Minutes
Multiply full hours by 60, then add the remaining minutes. For example, 8 hours 30 minutes is 8 × 60 + 30 = 510 minutes.
How to Calculate Overnight Work Hours
If an end time is earlier than the start time, it is treated as occurring the following day. A shift from 10:00 PM to 6:00 AM is therefore 8 hours.
How Break Time Is Deducted
Break hours and minutes are combined and removed only after gross duration is calculated. If a break is longer than the shift, the calculator shows an error and does not return a negative result.
Hours and Minutes to Decimal Hours
Divide minutes by 60 and add the result to the full hours. Thirty minutes is 0.50 hour, 45 minutes is 0.75 hour, and 7 hours 45 minutes is 7.75 hours.
Frequently Asked Questions
How do I calculate hours between two times?
Enter the start and end time. The calculator converts both to minutes and displays the elapsed hours and minutes.
Can the calculator handle overnight shifts?
Yes. End times earlier than start times are automatically treated as occurring the next day.
How do I subtract a lunch break?
Enter the unpaid lunch duration in the break hours and break minutes fields. It is subtracted from gross time.
What is 30 minutes as a decimal hour?
Thirty minutes is 0.50 decimal hour.
What is 45 minutes as a decimal hour?
Forty-five minutes is 0.75 decimal hour.
How many minutes are in eight hours?
There are 480 minutes in eight hours.
How are weekly overtime hours calculated?
Hours above the selected weekly threshold are overtime. Overtime never displays as a negative value.
Can I calculate multiple shifts?
Yes. Add up to 20 entries and the calculator totals their net time, minutes, decimal hours, and average duration.