Add or subtract time from a date
Pick a start date, add or subtract, and enter an amount. Use days, weeks, months, or years.
How to add days to a date
Adding days and weeks is plain counting on the calendar: 1 week is 7 days, and the tool steps through months of 28, 29, 30, and 31 days one by one. Adding months or years keeps the same day of the month and only adjusts when that day does not exist in the target month.
To measure the gap between two dates you already know, use the days between dates calculator. To see how many days are left until a holiday or a deadline, try the countdown calculator.
Dates X days from today
| Days added to 11/06/2026 | New date | Day of the week |
|---|---|---|
| 7 days | 11/13/2026 | Friday |
| 14 days | 11/20/2026 | Friday |
| 30 days | 12/06/2026 | Sunday |
| 60 days | 01/05/2027 | Tuesday |
| 90 days | 02/04/2027 | Thursday |
| 180 days | 05/05/2027 | Wednesday |
Month ends, leap years, and deadlines
| Math | New date | Day of the week |
|---|---|---|
| 11/06/2026 + 2 weeks | 11/20/2026 | Friday |
| 01/31/2026 + 1 month | 02/28/2026 | Saturday |
| 02/29/2024 + 1 year | 02/28/2025 | Friday |
| 03/01/2026 − 1 day | 02/28/2026 | Saturday |
- Day 31 plus 1 month: when the next month is shorter, the result is that month's last day (01/31 becomes 02/28, or 02/29 in a leap year).
- February 29 plus 1 year: in a non-leap year, the result is February 28.
- Deadlines counted in days usually leave out the start day. Because the tool adds to the start date, the start day itself is not counted.
- "Business days" are not skipped here. Weekends and holidays are counted like any other day.
Frequently asked questions
What is the date 90 days from today?
Enter today as the start date, type 90, and keep the unit on days. From Friday, November 6, 2026, 90 days later is Thursday, February 4, 2027.
How do I add days to a date?
Type the start date, choose Add, enter the number of days, and read the new date. Adding 30 days to 11/06/2026 gives 12/06/2026.
How do I subtract days from a date?
Choose Subtract and enter the amount. Subtracting 1 day from 03/01/2026 gives 02/28/2026.
What date is 30 days from today?
Use 30 days as the amount with today as the start date. From November 6, 2026, the answer is December 6, 2026, a Sunday.
What happens when I add 1 month to January 31?
The result is the last day of February, since the 31st does not exist there. In 2026 that is 02/28/2026.
How do I add weeks or months to a date?
Switch the unit to weeks or months. A week is 7 days, and a month keeps the same day number in the following month when that day exists.
Sources and method
Standard public-domain formulas. Every calculation is checked against independent numeric tests before it goes live.