Time Duration Calculator

The time between two times, adding and subtracting time, and totalling durations.

Time between two times

Start End Unpaid break (min)

8 hours 30 minutes

8.50 decimal hours · 8:30:00 · 510 minutes

Add or subtract time

Time Action Duration

11:45 AM

same day

Add up durations (one per line)

Durations

4 hours 30 minutes

4.50 decimal hours · 4:30:00 · 3 entries

Everything stays on this device — what you enter never leaves your browser.

Time duration calculator

This time duration calculator works out the time between two times: 9:00 am to 5:30 pm is 8 hours 30 minutes, or 8.50 hours. A shift that runs past midnight is handled for you: 10 PM to 6 AM is 8 hours.

Add time and subtract time

To add time, enter a start time and a duration such as 2h 45m: 9:00 am plus 2h 45m is 11:45 AM. Choose subtract to go backwards; if the answer falls on another day the calculator says so.

Hours calculator and time difference

As an hours calculator, paste a list of durations and get the total in hours and minutes and in decimal hours. For a full week with overtime and pay, use the time card calculator; for 24-hour times see the military time converter. The time difference is shown as words, h:mm:ss, decimal hours and total minutes.

Frequently asked questions

How do I calculate the time between two times?

Subtract the start from the end, borrowing 60 minutes when the end minutes are smaller. From 9:00 am to 5:30 pm is 8 hours 30 minutes, which is 8.50 hours or 510 minutes. Enter the two times above and the difference appears, written as words, as h:mm:ss and as decimal hours for payroll.

How do I calculate a time duration over midnight?

When the end time is earlier than the start time, the period crosses midnight, so add 24 hours to the end before subtracting. From 10 PM to 6 AM is 8 hours: 2 hours until midnight plus 6 hours after it. The calculator does this automatically whenever the end is earlier than the start; if the times are identical it reports zero.

How do I add hours and minutes together?

Add the hours and the minutes separately, then carry every 60 minutes into an hour. 1:30 plus 2h 15m plus 45 min is 4 hours 30 minutes, or 4.50 decimal hours. Put one duration per line in the list box and the total updates; formats can be mixed, and any line it cannot read is flagged with its line number.

How do I convert minutes to decimal hours?

Divide the minutes by 60. 45 minutes is 0.75 hours, 30 minutes is 0.50 and 15 minutes is 0.25. Timesheets and payroll use decimal hours because they multiply directly by a pay rate; every result here shows decimal hours next to the hours-and-minutes form.

How do I subtract time from a clock time?

Choose subtract in the add-or-subtract box. 9:00 AM plus 2h 45m is 11:45 AM, and subtracting works the same way backwards. If the result passes midnight the calculator says so: 10:00 PM plus 3h is 1:00 AM on the next day, and 1:00 AM minus 2h is 11:00 PM on the previous day.

Is my time data uploaded or processed on a server?

No. The calculations run inside this page, so what you enter never leaves your browser, and there is no sign-up. That is enforced rather than promised: this site’s test suite scans the shipped HTML for every browser API capable of sending data off the page and fails the build if it finds one.