Add or subtract days, weeks, months or years from a date.
This calculator adds days, weeks, months or years to a date, or subtracts them, and shows the resulting date. It is useful for finding a due date, a notice-period end, a warranty expiry, a renewal date or a date that was a fixed number of days ago.
If the next month is shorter, the date rolls forward into the following month. For example, adding one month to 31 January gives a date in early March. Check month-end dates by hand.
Yes. Choose the subtract option to go back in time from the starting date.
Select a starting date, choose Add or Subtract, enter a number and pick a unit: days, weeks, months or years. The calculator returns the new date. Days and weeks are exact calendar steps, and months and years move the calendar by that many months or years.
When the starting day does not exist in the target month, the date rolls forward. For example, adding one month to 31 January 2026 gives 3 March 2026, because February 2026 has only 28 days. If your deadline depends on month-end rules, check the result carefully.
Add 90 days: Starting on 10 October 2026, adding 90 days gives 8 January 2027.
Subtract 6 months: Starting on 10 October 2026, subtracting 6 months gives 10 April 2026.
Add 2 weeks: 14 days after 10 October 2026 is 24 October 2026.
Select today's date, choose Add, enter 30 and choose Days.
Yes. Choose Subtract to find a date before the selected date.
The calendar rolls forward when the next month is shorter. January 31 plus one month becomes March 3 in a non-leap year.
No. It counts all calendar days. For working days, adjust the result manually.