Julian Period year
A year number from 1 through 7,980.
Scaliger’s 7,980-year cycle
Julian Period Converter
Cycle Year
Enter a year on either side. The other side updates automatically using only the Julian calendar—never the Gregorian calendar.
Julian calendar year
BCE or CE, with no year zero.
Cycle Combination
Choose one number from each cycle to find the unique Julian Period year and its corresponding Julian calendar year.
Period year: 6,739
Calendar year: 2,026 CE
How the conversion works
Julian Period year 1 is Julian calendar year 4713 BCE. The current 7,980-year period therefore runs from 4713 BCE through 3267 CE; a new cycle begins in 3268 CE.
The simplest formula uses astronomical year numbering:
astronomical year = Julian Period year − 4713
In that internal numbering, astronomical year 0 means 1 BCE, −1 means 2 BCE, and +1 means 1 CE. The displayed Julian calendar result uses ordinary BCE/CE notation and never displays a year zero.
For Julian Period year Y, each cycle number is ((Y − 1) mod cycle length) + 1. Since 15, 19, and 28 are pairwise coprime, the Chinese remainder theorem gives one unique year from 1 through 7,980 for every combination.
Uses the proleptic Julian calendar for the BCE portion of the period.