Date & Time Calculator

Time Calculator

Add or subtract hours and minutes from a time of day.

Operation

Resulting time

12:15 PM

How it works

Enter a starting time and a duration to add or subtract. The result wraps around midnight automatically — adding 3 hours to 11:00 PM correctly gives 2:00 AM the next day.

Formula

Resulting time = Start time ± Duration, wrapped to a 24-hour clock

Example

9:30 AM plus 2 hours 45 minutes is 12:15 PM.

Frequently asked questions

Does this tell me the date, not just the time?

No — this only tracks the time of day and wraps around midnight. If you also need to know which calendar date you land on, use the Date Calculator alongside this one.

Can I subtract past midnight?

Yes — subtracting a duration that goes before midnight correctly wraps to the previous day's time.