Date Difference Calculator
Find the number of days, weeks, months, and years between any two dates — useful for deadlines, anniversaries, and project planning.
Choose both dates
How the calculation works
The total-days figure is a simple subtraction in milliseconds divided by the length of a day. The years/months/days breakdown uses calendar arithmetic — months don't have a fixed length, so the tool borrows from the actual length of the previous month (which handles leap years correctly).
Useful for
Counting down to deadlines, planning project timelines, calculating notice periods, or just settling a bet about how long ago something happened.