Date Difference Calculator

Find the difference between two dates in years, months, weeks, and days. Select your dates and get accurate calendar-based results instantly.

Start Date

End Date

Include the end date in the calculation

Select a start date and an end date.

Note: The calculator uses calendar dates rather than fixed 30-day months. Leap years and different month lengths are accounted for. Including the end date adds one day to the overall interval.

How to Calculate the Difference Between Dates

Choose your start date and end date, then click Calculate Difference. The calculator shows the exact number of days, the equivalent complete weeks, and a calendar-based breakdown of years, months, and days.

For example, the difference between January 1 and January 31 is 30 days when the starting day is excluded. If you select Include the end date, the result becomes 31 days. The calculator works for past and future dates, including leap years.