Date adjustment
Add or Subtract Dates
Build a clear calendar operation and preview the resulting date and weekday.
Adjust a date
Choose a starting date, an operation, and the amount of time to add or subtract.
The date adjustment calculator moves a starting date forward or backward. Calendar mode supports years, months, weeks and days, while business-day mode skips configured weekends and exclusions.
How to add or subtract time
- 1Choose a starting date and whether to add or subtract.
- 2Select calendar time or business days.
- 3Enter the amount and calculate the resulting date and weekday.
Common uses
- Finding a due date after a fixed period
- Moving a date by business days
- Calculating renewal or follow-up dates
- Checking the weekday of a future or past date
Calendar dates and end-of-month rules
Calendar units are applied in order: years, months, weeks and days. When a target month does not contain the original day, DateKit uses the last valid day of that month.
Business-day mode moves one valid working day at a time and ignores selected weekends and custom exclusions.
Add or subtract date questions
What happens when I add one month to January 31?
DateKit uses the last valid day of the target month, so the result is February 28 or February 29 in a leap year.
Can I combine years, months, weeks and days?
Yes. In calendar mode, enter any combination of the four units.
Do business days skip custom holidays?
Yes, when those dates are entered in the custom exclusions field.
Keep calculating