Date calculator

This date calculator does two common jobs. The first tab finds the exact time between two dates — in days, weeks, and in years, months and days. The second tab adds or subtracts a number of days from a date to find a past or future date, and tells you which day of the week it falls on.

Working out durations

Use the difference tool for deadlines, project planning, holidays, anniversaries, and counting down to events. It accounts for leap years and different month lengths automatically, so the day count is always accurate. To add or subtract dates, the second tab is ideal for finding due dates, notice periods, and reminders.

Related tools

For age specifically, use our age calculator; for time-of-day arithmetic, the time calculator; and to convert between days, weeks, months and years, the calendar time converter.

Frequently asked questions

How do I subtract days from a date?

Use the “Add / subtract days” tab and enter a negative number, for example −14 to go back two weeks.