Add Days to Date Calculator

Use this add days to date calculator to move forward or backward on the calendar without counting days by hand. It is useful for deadlines, invoices, shipping estimates, travel planning, study schedules, contracts and any task where you need a quick future or past date.

Pick the starting date, choose whether to add or subtract days, and enter the number of days. The result includes the new date, the weekday, the day of the year and the ISO week so you can double-check work calendars, project timelines and international date references.

If you need to compare different scenarios, change the number of days and run the calculation again. This makes it easy to test due dates, return dates, grace periods and delivery windows in a few seconds.