How dates and observances are verified
If a date, recurrence, jurisdiction or organizer cannot be confirmed from reliable evidence, we leave it unverified rather than guessing.
Source quality
Primary and first-party sources are preferred: governments, intergovernmental bodies, organizers, professional associations, faith communities, institutional archives and documented creators. Secondary sources are used when they add useful corroboration.
How recurring dates are handled
Fixed and clearly calculable patterns can carry forward to future years. Edition-specific, variable and historical dates are checked separately instead of being assumed.
Scope and status
An observance name does not prove government recognition, worldwide scope or public-holiday status. Country and organizer boundaries are preserved from the sources.
When evidence is unclear
We leave uncertain information unpublished rather than repeating a date simply because it appears on other calendars.
Editorial content
History, activities, messages, captions, quotes and similar material are reviewed separately so they never replace or alter the factual source information.