How Long Between Two Times?
This free time duration calculator tells you exactly how much time passes between a start time and an end time — in hours and minutes, and as a decimal number of hours. Enter the two times above and get the answer instantly. It even handles overnight periods that cross midnight, which makes it ideal for work shifts, sleep tracking, cooking, and time sheets.
How to Use the Time Duration Calculator
- Enter the start time.
- Enter the end time.
- Press Calculate to see the duration in hours and minutes, plus the total in decimal hours.
If the end time is earlier than the start time, the calculator assumes the period runs overnight and adds the hours past midnight automatically.
How Time Duration Is Calculated
The tool converts each time to the number of minutes since midnight, subtracts the start from the end, and converts the result back into hours and minutes. For example, from 9:00 to 17:30 is 8 hours 30 minutes (8.5 hours). From 22:00 to 6:00 crosses midnight, so it is 8 hours.
Decimal Hours for Payroll
Many time sheets and payroll systems want hours in decimal form rather than hours-and-minutes. The calculator gives you both. As a quick reference: 15 minutes = 0.25 hours, 30 minutes = 0.5 hours, and 45 minutes = 0.75 hours. So a shift of 8 hours 15 minutes is 8.25 hours.
Why Use a Time Duration Calculator?
Working out elapsed time in your head is error-prone, especially across the noon and midnight boundaries or when minutes do not divide evenly. A duration calculator removes the guesswork for hourly workers logging shifts, freelancers billing clients, students timing study sessions, and anyone tracking how long something actually took. Because it converts to decimal hours too, it slots straight into spreadsheets and invoices.
Frequently Asked Questions
How do I calculate hours between two times?
Subtract the start time from the end time. The calculator above does it instantly and converts the result to hours, minutes, and decimal hours.
Does it work for overnight shifts?
Yes. If the end time is before the start time, it assumes the period crosses midnight and adds the time correctly.
How do I convert minutes to decimal hours?
Divide the minutes by 60. 30 minutes = 0.5 hours; 45 minutes = 0.75 hours.
Subtracting Break Time
For work shifts, you usually need paid hours, which means subtracting unpaid breaks. First calculate the full duration between clock-in and clock-out, then subtract your break in minutes. A shift from 9:00 to 17:30 is 8 hours 30 minutes; take off a 30-minute lunch and you have 8 paid hours. Converting to decimal (8.0) makes it drop straight into a payroll spreadsheet.
Decimal Hours Reference
Payroll systems almost always use decimal hours, and rounding minutes by hand causes errors. Use these conversions: 10 minutes = 0.17, 15 minutes = 0.25, 20 minutes = 0.33, 30 minutes = 0.5, 40 minutes = 0.67, and 45 minutes = 0.75. So 7 hours 20 minutes is 7.33 hours. The calculator gives you the decimal value automatically alongside the hours-and-minutes result.
Times That Cross Midnight
Overnight shifts and late sessions are where mental math breaks down. If you start at 22:00 and finish at 6:00, simple subtraction gives a negative number. The calculator detects this and adds a full day, returning the correct 8 hours. This makes it reliable for night-shift workers, hospital rotations, security logs, and anyone tracking time that runs from one calendar day into the next.
Everyday Duration Examples
A few common results help you sanity-check the tool: 9:00 to 17:00 is 8 hours; 8:30 to 12:15 is 3 hours 45 minutes (3.75 hours); 23:00 to 7:00 is 8 hours across midnight; and 14:20 to 16:05 is 1 hour 45 minutes. Whether you are logging a work shift, timing a long drive, tracking how long a recipe simmered, or measuring sleep, the same calculation applies. Enter the two clock times above and you get the exact gap in hours and minutes, plus the decimal hours that payroll and spreadsheets expect.