Weeks Calculator
Add or subtract weeks from a starting date to find the resulting calendar date. Useful for deadlines, schedules, appointments and planning dates weeks ahead or behind.
How to Add or Subtract Weeks From a Date
One week is always seven days. This calculator multiplies your number of weeks by seven, then moves the calendar date forward or backward by that many days.
Month and year boundaries, including leap years, are handled automatically — you do not need to count days by hand.
- 1 week from 08/20/2026 = 08/27/2026
- 4 weeks from 08/20/2026 = 09/17/2026
- 2 weeks before 08/20/2026 = 08/06/2026