About Time Addition Calculations

Adding time intervals is essential for project planning, scheduling meetings across time zones, calculating work hours, and determining deadlines. This calculator handles time arithmetic using JavaScript's native Date object, ensuring accurate results across daylight saving time changes and month boundaries.

How to Use

Enter a base time (defaults to current time)
Enter a numeric value to add or subtract
Select hours, minutes, or seconds as your unit
Click Add or Subtract to calculate

Examples

Adding 2.5 hours to 14:00 gives 16:30
Subtracting 90 minutes from 10:00 gives 08:30
Adding 3600 seconds to 23:59:00 gives 00:59:00 next day

Time Conversion Reference

Unit	In Seconds	In Minutes	In Hours
1 Hour	3600	60	1
1 Minute	60	1	0.0167
1 Second	1	0.0167	0.000278

Important Notes

Daylight saving time changes may cause apparent discontinuities. Month boundaries and leap years are handled automatically. Negative values subtract time.

Frequently Asked Questions

Does this handle daylight saving time changes?

Yes, the JavaScript Date object automatically adjusts for DST transitions when adding time intervals.

How are month endings handled?

Adding time that crosses month boundaries automatically rolls over to the next month (e.g., Jan 31 + 1 day = Feb 1).

Can I use decimal values?

Yes, you can enter decimal values for hours (e.g., 1.5 hours = 90 minutes).

Time Add Calculator

Result

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Time Add Calculator Add Hours Minutes or Seconds

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