Time Duration Calculator
Calculate the number of hours and minutes between a start time and end time.
About the Time Duration Calculator
Calculating hours worked, meeting lengths, or event durations by hand often leads to off-by-one errors — especially when times cross noon. The Time Duration Calculator handles all that arithmetic in under a second.
How It Works
Enter a start time and end time using 24-hour (HH:MM) or standard AM/PM format. Optionally enter any break duration in minutes. The tool computes the total elapsed time minus the break, showing results in hours and minutes as well as decimal hours (useful for payroll or billing).
Decimal Hours for Payroll
Many payroll systems require time in decimal format. 8 hours 30 minutes = 8.5 hours. 7 hours 45 minutes = 7.75 hours. Use the decimal output from this tool to fill overtime sheets or freelance invoices accurately.
Common Scenarios
Work shifts: Start 8:30, end 17:00, with a 45-minute lunch. Net work time = 7 hours 45 minutes = 7.75 hours.
Project billing: A consulting call ran 9:15 to 11:40 with no break — 2 hours 25 minutes = 2.42 hours billable at your hourly rate.
Cooking and baking: You put a roast in at 1:30 PM and plan to eat at 6:00 PM — that's 4 hours 30 minutes of cook time.
Study sessions: Track focus blocks. Started at 7:00 AM, ended 9:45 AM = 2 hours 45 minutes of deep work.
Overnight Shifts
This tool automatically handles overnight durations. A shift from 22:00 to 06:30 the next morning calculates correctly as 8 hours 30 minutes.
Converting Minutes to Hours
To convert any minute count to hours: divide by 60. 150 minutes ÷ 60 = 2.5 hours. The tool does this automatically so you never make rounding errors on your timesheet.