Imperial Dating System

Overview

The Imperial Dating System is the date formatting system used in the Warhammer 40k universe. It is intrinsically based on the Gregorian calendar for its epoch and years.

The first digit represents the in-universe location of the event, with 0 representing events that took place on Terra (Earth). The next set of 3 digits represent the fraction of the current year that has passed, in hundredths.

After that, the final set of 3 digits represents the current year in the Gregorian calendar, truncated to the last three digits. The current millennium, denoted with a capital M, is the current millennium in the Gregorian calendar, starting with M1 at the year 0 BCE.

Info

Since this website is located on Terra (Earth), the first digit will always be 0.

This calendar considers the beginning of a millennium to be on year 1 (e.g. 2001 rather than 2000), so the final year of any millennium is written as 000.

Accuracy

This calculation is exactly accurate, as it is based on the Gregorian calendar and its year calculations. There is a bit of uncertainty regarding the handling of years before the Gregorian epoch, but that is outside the range of this calendar anyway.

Source

This calculation was sourced from the Warhammer 40k Fandom Wiki.