Add / Subtract Days
Add or subtract any number of days, weeks, or months from a date.
CalculatorHow to use this tool
Move a date forward or backward by any mix of years, months, weeks, and days, and see the resulting weekday. Useful for contract dates, notice periods, and anything specified as "90 days from signing".
- STEP 1Enter the starting date.
- STEP 2Choose Add or Subtract.
- STEP 3Fill in any combination of years, months, weeks, and days, then calculate.
Years and months are applied as calendar steps before weeks and days. When the target month is shorter, the result clamps to its last day — 31 January plus one month is 28 February.
All inputs and calculations stay in your browser; TimeKit does not send your entries to a server.
Examples
Frequently asked questions
Why is 31 January plus one month not 3 March?
Adding a month means the same day number in the next month. February has no 31st, so the result clamps to the last valid day instead of spilling into March.
Does the order of the fields matter?
Yes. Years and months are applied first, then weeks and days, which is the convention contracts normally assume.