📅
Date Calculator
D-Day, Days Between Dates, and N-Days Before/After Calculator
Total Days Between Dates
D-100 (100 days)
approx. 14.3weeks · approx. 3.3months
Date intervals and D-Day counts
Counting days to an exam, the span left on a contract, or the date 90 days from now is where leap years and month ends trip people up. This calculator works out the number of days between two dates, a D-Day countdown, and the date N days before or after a given one.
How to use it
- Pick your reference date.
- Add an end date for an interval, or a number of days to shift forward or back.
- Read the resulting date and the elapsed day count.
Frequently asked questions
- Does a D-Day count include the day itself?
- A D-Day normally treats the target day as zero and counts the days remaining. When a contract term has to include the first day, add one to the result.
- Are leap years handled?
- Yes. Years containing 29 February are accounted for exactly.