Time Calculator
Add or subtract two lengths of time in hours, minutes and seconds.
Result…
How it's calculated
Seconds = h × 3600 + min × 60 + s Result = first ± second, then back to h, min, s
Turns both times into seconds, adds or subtracts them, and turns the answer back into hours, minutes and seconds. Minutes and seconds over 60 are fine: 90 minutes counts as 1 h 30 min. A subtraction that goes below zero shows a minus sign.
Your numbers, step by step
About the Time calculator
This time calculator adds or subtracts two lengths of time given in hours, minutes and seconds. It turns both into seconds, does the sum, and turns the answer back into hours, minutes and seconds. It also shows the total in seconds, minutes and hours, and in days with hh:mm:ss. Use it to total video or audio lengths, workout and lap times, travel legs or time spent on tasks. You don't have to tidy your inputs first: 90 minutes is read as 1 hour 30 minutes. If you subtract a longer time from a shorter one, the result shows a minus sign instead of an error. For clocking in and out across a day, the hours calculator is a better fit.
How to use it
- Enter the first length of time in “First: hours”, “First: minutes” and “First: seconds”.
- Choose Add + or Subtract − under “Operation”.
- Enter the second length of time.
- Read the result in hours, minutes and seconds, plus the totals in seconds, minutes, hours and days.
Worked example
1 h 45 min 30 s + 2 h 30 min 45 s = 4 h 16 min 15 s, which is 15,375 seconds or about 4.27 hours. Adding 20 hours to 6 hours 90 minutes gives 27 h 30 min, shown as 1 day 3:30:00.
Updated
Questions people ask
How do I add hours and minutes together?
Add the minutes and the hours separately, then carry every 60 minutes over as one hour. The calculator does this by converting everything to seconds first, so nothing gets lost.
How do I convert minutes to hours?
Divide the minutes by 60. 90 minutes is 1.5 hours, or 1 hour 30 minutes.
Can I enter more than 60 minutes or seconds?
Yes. Values over 60 are carried over, so 6 hours 90 minutes is treated as 7 hours 30 minutes.
What happens if I subtract a bigger time from a smaller one?
You get a negative answer with a minus sign. 1 hour minus 2 hours 30 minutes is −1 h 30 min.
How do I see a long total in days?
Read the “Days, h:mm:ss” line. 27 hours 30 minutes is shown as 1 day 3:30:00.