Holocene calendar

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"Holocene era" redirects here. For the geological epoch, see Holocene.

The Holocene calendar, also known as the Holocene Era (HE) or Human era, is a year numbering system that adds exactly 10,000 years to the currently world-dominant Anno Domini (AD) or Common Era (CE) system, placing its first year near the beginning of the Holocene epoch and the Neolithic revolution. Human Era proponents claim that it makes for easier geological, archaeological, dendrochronological and historical dating, as well as that it bases its epoch on an event more universally relevant than the birth of Jesus. The current year of AD 2014 can be transformed into a Holocene year by adding the digit "1" before it, making it 12014 HE. The Human Era was first proposed by the scientist Cesare Emiliani in 1993.[1][2][3]


Cesare Emiliani's proposal for a calendar reform sought to solve a number of alleged problems with the current Anno Domini era, which number the years of the commonly accepted world calendar. These issues include:

  • The Anno Domini era is based on an erroneous estimation of the birth year of Jesus Christ. The era places Jesus' birth year in 1 BC, but modern scholars have determined that he was born in or before 4 BC. Emiliani argues that replacing it with the approximate beginning of the Holocene era makes sense.
  • Emiliani opined that the birth of Jesus Christ is a less universally relevant epoch event than the approximate beginning of the Holocene era.
  • The years BC are counted down when moving from past to future, making calculation of timespans difficult.
  • The Anno Domini era has no year zero, with 1 BC followed immediately by AD 1, complicating the calculation of timespans further.

Instead, HE places its epoch to 10,000 BC. This is a rough approximation of the start of the current geologic epoch, the Holocene (the name means entirely recent). The motivation for this is that human civilization (e.g., the first settlements, agriculture, etc.) is believed to have arisen entirely within this time. All key dates in human history can then be listed using a simple increasing date scale with smaller dates always occurring before larger dates.


Conversion to the Human Era from Julian or Gregorian AD years can be achieved by adding 10,000. BC years are converted by subtracting the BC year from 10,001.

A useful validity check is that the last single digits of BC and HE equivalent pairs must add up to 1 or 11.

Gregorian years ISO 8601 Human Era
Holocene Epoch
30001 BC −30000 20000 BHE
10001 BC −10000 0 HE
10000 BC −9999 1 HE
9001 BC −9000 1000 HE
1000 BC −0999 9001 HE
100 BC −0099 9901 HE
2 BC −0001 9999 HE
1 BC +0000 10000 HE
1 AD +0001 10001 HE
2 AD +0002 10002 HE
2014 AD +2014 12014 HE
10000 AD +10000 20000 HE

See also[edit]


  1. ^ Cesare Emiliani, "Calendar Reform", Nature 366 (1993) 716.
  2. ^ The Holocene Calendar at Meerkat Meade.
  3. ^ Human Era Calendar by Harry Weseman.