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Date

D-Day Calculator

D-Day rules

The D-Day calculator compares a base date with a target date and expresses the distance as today, D-N, or D+N.

The target date is the anchor. Dates before it are shown as remaining time, and dates after it are shown as elapsed time.

How to read the result

D-Day means the base date and target date are the same calendar date.

D-N means the target is still ahead. D+N means the target date has already passed.

Examples

Exam or launch countdown

Set the target date to the important day and check the remaining distance from today.

Anniversary tracking

Use the same calculation to see how many days have passed after a date.

Limits

  • D-Day is a date-distance display, not a calendar notification system.
  • Business-day countdowns belong in the workday calculator.
  • The URL stores the base and target dates.
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