Date & Time
D-Day Calculator
Choose a reference date and target date to see how many calendar days remain, or how many have passed.
How to use
Enter the values requested above and choose a calculation option. Choose a reference date and target date to see how many calendar days remain, or how many have passed. The result is calculated in your browser.
Formula
D-day count = target date − reference date, measured in calendar days.
Example
If the target is 10 days after the reference date, what is the result?
The target is D−10: ten days remain.
Frequently asked questions
- Is the target day counted as a full remaining day?
- The result is the calendar-day difference between the two dates; the target date itself is D-Day.
- Are my entries stored?
- No. The calculation runs in your browser, and this page does not save the values you enter.