Add or Subtract Days, Weeks, Months and Years From a Date
Moves a date forward or back by any mix of years, months, weeks and days.
Share sends a link that reopens these numbers. Copy details pastes the full breakdown as a list.
The formula
date + years and months, keeping the day of the month then + weeks × 7 + days
If the new month is too short to have that day, the result is the last day of that month.
What to watch out for
A week is always 7 days. Months and years follow the calendar, so the number of days they add depends on where you start. To skip weekends, use the deadline date calculator.
Frequently Asked Questions
What is 31 January plus one month?
The last day of February: 28 February 2025 in 2025 and 29 February 2024 in a leap year. It does not spill into March.
What is 29 February plus one year?
28 February 2025, the last day of February in a year without a 29th.
Does the order of adding matter?
It can, because months are different lengths. Here months come first: 31 January 2025 plus 1 month and 1 day is 1 March 2025.