Help:Converting Time

The general formula for a relatively accurate conversion (within a few years) on the scale of a few thousand years is very simple.

Earth to Universalis:
(year - 1399.7857) * 8/5

Universalis to Earth:
year * 5/8 + 1399.7857

For more accurate numbers use 365.2425/228.527477 and its inverse.

Example

(current Gregorian decimal year-base Gregorian decimal year) * mean Gregorian year in solar Earth days/sidereal Universalis year in solar Earth days

(2016-1399.7863) * 365.2425/228.527477

984.859393 (Universalis decimal year)