Add or subtract days, hours, minutes and seconds, or add a duration to a clock time to find when something ends, including past midnight.
About this tool
Add or subtract hours, minutes and seconds, or add time to a clock time.
How to use Time Calculator
- Choose Add durations or Add to a clock time.
- Enter the first duration or start time, then choose add or subtract.
- Enter the second duration and read the result.
Worked example
A flight leaving at 9:30 PM that lasts 7 h 45 min lands at 5:15 AM the next day (in the same time zone).
Can the result be negative?
Yes. Subtracting a longer duration gives a negative result.
Does it handle time zones?
No. Use the time zone converter for that.
- Time Calculator — Add or subtract hours, minutes and seconds, or add time to a clock time.
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