Culture calendar
December 21 in 2026
December 21 is day 355 of 365 and falls in ISO week 52.
21
December · Monday
Day of year355
ISO week52
Days after10
Source & method: Calendar facts are calculated locally. Historical events and birthdays are intentionally omitted until an editorial source workflow is connected.
About this calendar
A clearer way to see on this day.
A date’s place in the year, with carefully sourced context. MixCalendar keeps the underlying time data separate from the visual layout, so the same calendar can grow into new formats without changing its meaning.
Good to know
Where are the historical facts?
MixCalendar only publishes historical facts after editorial review with traceable sources. Phase 1 currently provides verified calendar facts.
Does this page change each year?
Weekdays, week numbers, and day counts are calculated for the current year.
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