Date Difference Calculator

The number of days between two dates is useful for deadlines, travel, contracts, anniversaries, and project planning. Calendar months make the same interval harder to express because they have different lengths.

This calculator shows the exact total number of midnights crossed and also decomposes the interval into whole calendar years, months, and days.

Dates are calculated as calendar values rather than local timestamps, so daylight-saving transitions cannot add or remove an hour and distort the day count.

Enter either date first. A negative total indicates that the second date comes earlier.