The Anniversary Collection gathers public holidays, Korean national observances, fun couple/friend days, and widely recognized international days on one page, sorted by upcoming D-day. No input is required — just toggle categories or search.

Fixed solar-calendar holidays (New Year's Day, Independence Movement Day, Children's Day, Memorial Day, Liberation Day, National Foundation Day, Hangeul Day, Christmas) are included along with lunar-calendar holidays such as Lunar New Year, Chuseok, and Buddha's Birthday, whose solar date changes every year. Lunar holidays are converted to the correct solar date using the lunar-solar conversion module.

Korean observances are national days that aren't public holidays but are marked every year, like Workers' Day, Parents' Day, and Teachers' Day. Fun days are couple/friend dates such as Valentine's Day, White Day, and Pepero Day. International days are widely known worldwide, such as International Women's Day, Earth Day, and Halloween.