D-Day Counter

Count the days until a target date as D-N, D-DAY or D+N, and keep a list of events saved in your browser.

How to use

Pick a target date. Add a title so it is easy to recognise in the saved list.
The result shows instantly as D-N, D-DAY or D+N, together with the days remaining and the weekday.
Switch on ‘Include today’ to count today as day one.
Press ‘Save’ to keep the event, and ‘Delete’ in the list to remove it.

What does ‘Include today’ change?

It counts today as day one, so a date three days away shows as D-4 instead of D-3.

Does it count dates in the past?

Yes. If the target date has passed, you get D+N showing how many days ago it was.

Where is my saved list kept?

In this browser's local storage only. It is never uploaded and is not shared with other devices.

Does it work in private mode?

The calculation always works; saving may be blocked, and you will see a note when it is.

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