Anniversary Calculator
Enter a start date to get milestone dates (100/200/1000 days, 1st/10th anniversaries) with countdowns. Follows the Korean convention of counting the start date as day 1. Everything runs in your browser.
Enter the start date (e.g. relationship, founding day)
FAQ
How is the 100th day counted?
Korean convention counts the start date as day 1, so the 100th day is start + 99 days.
Which comes first, anniversaries or day counts?
Results are sorted by date. The 1000th day lands around 2 years 9 months—before the 3rd anniversary.
Are past milestones shown?
Milestones passed within the last year stay visible; older ones are hidden. The running day count always shows.
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