What is a kiloday?
A kiloday is a thousand days of being alive. Kilo means thousand, as in kilogram and kilometre, so your 1st kiloday is day 1,000, your 2nd is day 2,000, and so on. They come about every 2 years and 9 months, so they land in a different season each time.
Kiloday or kday?
Both. Kiloday is the word, and kday is how we count them out loud. "Your 17th kday" is your 17th kiloday: 17,000 days.
Why celebrate them?
Birthdays come every year, on the same date, and everyone knows when. Kilodays are rarer, move around the calendar and are hard to guess, which makes them perfect for a surprise. Along the way there are fun-number days too, like 11,111, 12,345 and 31,415 (your π day).
How we count
- Your birth date is day 0. The day after is day 1, so day 1,000 falls exactly 1,000 days after you were born.
- Leap days count like any other day, because we count real calendar days, not years.
- We count whole days in your own calendar, so the time of birth and time zones don't change the date.
- Other calculators that call your birth date day 1 will land one day earlier. Neither is wrong; we picked day 0 so day 1,000 means a thousand full days.
Not just birthdays
Any date that matters has kilodays: a wedding, the day you met, the day you moved, the day you got sober. Missed an anniversary? Its next kiloday is a fine way to make up for it.
Find yours
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