Add or Subtract Days

Start Date

Operation

Amount

Unit

Choose a date and operation, then click Calculate

How to Add or Subtract Days from a Date

Choose a start date, select whether to add or subtract, enter an amount, and pick your unit (days, weeks, months, or years). The resulting date updates instantly as you change the inputs.

When adding months, the calculator handles month-length differences automatically. For example, adding 1 month to January 31st gives February 28th (or 29th in a leap year), since February doesn't have 31 days.

Looking for a quick answer? Try our Days From Today calculator for common intervals like 30, 60, or 90 days from now.