All calendars start at year 1 on the same day, and there’s no way to define a correspondence between them. So year 1 of every calendar correspond to every others' year 1.
In practice, when working with multiple calendars (e.g., Gregorian, Persian, or a custom fantasy calendar), you need to be able to say:
“Day X, Year Y of Calendar A corresponds to Day Z, Year W of Calendar B.”
This would allow:
  • Proper alignment of historical events across different cultures.
  • Worldbuilding scenarios where different peoples measure time differently but still share a reference point.
  • More accurate conversion when using real-world inspired calendars.
Without anchor dates, every calendar is “floating” with respect to the others, which makes multi-calendar timelines very hard to manage.
Thanks Braden for your hard works ! Really love LegendKeeper so far it is an amazing tool!