Date Calculator
Pick a mode. Everything uses UTC so your answer isn’t shifted by time zones.
Mode
Add or subtract
Business days skip weekends only.
Difference between dates
We show both total days and Y/M/D on the calendar.
Notes
- “Business days” skip Saturdays and Sundays.
- Adding months clamps to the last valid day in the new month (Jan 31 + 1 month → Feb 28/29).
- All math is calendar-based in UTC to avoid local time offsets.