Date Difference Calculator
Math & EverydayThe gap between two dates in years, months, days — and every other unit.
Runs entirely in your browser — nothing is uploaded
Features
- Years, months and days, with month-end clamping done properly.
- Total days, weeks, months, hours and minutes.
- The weekday each date falls on.
- Results update as you type, with no button to press.
How to use the Date Difference Calculator
- 1Pick the two dates.
- 2Read the difference in calendar terms and in totals.
- 3Both orders work — it tells you if the second is earlier.
Frequently asked questions
How many days are between two dates?
The tool counts whole calendar days from the first to the second, exclusive of the start. Leap years are handled, and the arithmetic is done on calendar dates rather than timestamps so daylight-saving changes cannot add or lose a day.
Why is 31 January to 1 March "1 month, 1 day"?
Because whole months are counted first: 31 January plus one month lands on 28 February, since 31 February does not exist, and one more day reaches 1 March. Subtracting the day numbers and borrowing gives a wrong answer here.
Does it include both the start and end dates?
The total-days figure is the gap between them, so 1 January to 2 January is one day. For an inclusive count — as notice periods and project plans usually want — add one, or use the Working Days tool, which counts inclusively by design.