Choose the right mode
Add durations, compare two clock times, shift a clock time, or convert decimal hours.
Add or subtract durations, find the exact time between clock times, shift a clock time, or convert decimal hours — all without base-60 math in your head.
Blank values count as zero. Minutes and seconds over 59 are normalized automatically.
If the end time is earlier than the start time, the calculator treats it as the next day.
Useful for timesheets: 7.75 hours equals 7 hours 45 minutes, not 7 hours 75 minutes.
Add durations, compare two clock times, shift a clock time, or convert decimal hours.
Use days, hours, minutes, and seconds. Large minute or second values are normalized automatically.
Read the duration in h:m:s, decimal hours, total minutes, or total seconds and copy what you need.
Combine up to ten signed rows of days, hours, minutes, and seconds.
Calculate elapsed time across midnight without manually adding a day.
Move a starting clock time forward or backward and see the day offset clearly.
Convert timesheet-style decimal hours to hours, minutes, and seconds in either direction.
See normalized duration, decimal hours, total minutes, and total seconds together.
No account, no API call, and no time entries sent to a server.
Clock and duration math uses groups of 60 rather than groups of 10. That is why 2 hours 45 minutes plus 1 hour 30 minutes becomes 4 hours 15 minutes, not 3 hours 75 minutes.
Seconds carry into minutes.
Minutes carry into hours.
Clock times wrap at midnight.
If you are preparing work logs or timesheets, you can move the result into Motricialy's Online Excel Editor or Online CSV Editor without installing desktop software.
Each duration is converted to total seconds, the requested addition or subtraction is applied, and the result is normalized back into days, hours, minutes, and seconds.
In Time Between mode, the calculator treats the end as occurring on the next day. For example, 10:30 PM to 6:15 AM is calculated as an overnight duration.
Yes. The duration modes normalize those values automatically, so 90 minutes becomes 1 hour 30 minutes.
Decimal hours express fractions of an hour as decimals. For example, 7.75 hours equals 7 hours 45 minutes because 0.75 × 60 = 45.
No. The calculation logic runs locally in your browser, so your time values do not need to be uploaded.
Yes. Decimal hours are especially useful in timesheets, and you can continue working with them in Motricialy's Online Excel Editor.