D-Day Countdown Calculator
How many days until your date? Plus 100-day and 1-year anniversaries.
D-day countdown
Anniversaries (counted from the day you met)
About the D-Day Countdown Calculator
Choose a target date and the calculator shows how many days are left as D-minus a number, or D-plus a number for dates in the past. In the anniversary section, enter a start date (for example the day you met) to get the dates of the 100th, 200th, 300th, 500th and 1000th days and the 1st, 2nd, 3rd, 5th and 10th anniversaries, with weekdays. The date you enter is saved only in your own browser, so it is still there next time.
Frequently asked questions
How is D-day calculated?
It is the target date minus the reference date (today by default). The target day itself shows D-Day, and past dates show D-plus.
Is the 100th day 100 days later or 99 days later?
In Korea the first day counts as day 1, so the 100th day is 99 days after the start date. This calculator uses that convention.
How is the 1st anniversary decided?
It is the same month and day in the next year. If the start date is February 29, the date in non-leap years is March 1.
Is my date stored on a server?
No. Calculations happen inside your browser, and the target date, title and start date are stored only in your own browser (localStorage). Clearing browser data removes them.