BC and AD and BCE and CE are two labels for exactly the same years. BC means before Christ and AD means Anno Domini, while BCE means before the Common Era and CE means Common Era. Only the wording differs, not the dates.
Key takeaways
- BC and BCE name the same years, and so do AD and CE: 400 BC is 400 BCE and AD 2026 is 2026 CE [1].
- The system dates from about the year 525, when the monk Dionysius Exiguus set the starting point [1].
- There is no year zero, so 1 BC is followed directly by AD 1 [1].
- This site uses BC and AD, as in our dates 753 BC, 264 BC, 133 BC, 44 BC, AD 14, AD 117, AD 211, AD 395, AD 476, AD 565, AD 1000, AD 1180 and AD 1453.
How BC/AD and BCE/CE work
Both systems count years from the same starting point and run in the same direction. BC and AD (Anno Domini, "in the year of the Lord") put a label after or before the number. BCE and CE (Before Common Era, Common Era) do the same thing with different words. The two pairs refer to the same years: AD 2026 is 2026 CE, and 400 BC is 400 BCE [1].
The numbering goes back to about the year 525. A Christian monk, Dionysius Exiguus, set the year of Jesus's incarnation as the starting point for the church's calendar. He wanted to replace an older era counted from the persecutions under the emperor Diocletian [1]. The Venerable Bede helped to spread the system in England in 731 [1]. Bede also counted years before 1 backwards with no year zero, so 1 BC is followed directly by AD 1 [1]. That is why historians' subtraction across the boundary needs care.
"Common Era" is the newer label. Before it caught on, the older phrase "vulgar era" was often used for AD, where "vulgar" meant "of the ordinary people" and was not rude [1]. Critics of BCE and CE point out that both systems share the same starting point, so they are equally Christian in origin [1].
Usage varies. Many academics in archaeology, history and theology use CE, and Jewish scholarship has long used it [1]. In the UK, some local education authorities and parts of the BBC use it, while the National Trust and The Guardian keep BC and AD [1]. Neither is wrong.
An example from our data
This site uses BC and AD. Our key dates run 753 BC, 264 BC, 133 BC, 44 BC, AD 14, AD 117, AD 211, AD 395, AD 476, AD 565, AD 1000, AD 1180 and AD 1453. Two of them show how the labels work: 44 BC is when Julius Caesar is assassinated, and AD 14 is when Augustus dies. Read as BCE and CE they would be 44 BCE and 14 CE, the same moments.
We chose BC and AD because they are the labels most of our readers know and search for, and because it keeps every date on the site in one form. Our dates page lists them all.
The thing people get wrong
Some people think BCE and CE were invented to change the dates, or that they shift the calendar. They did not. Nothing moves. 753 BC and 753 BCE are the same year, and so are AD 476 and 476 CE [1]. The only difference is the wording, and which one you meet depends on who wrote the book or exam paper.
Frequently asked questions
Is BCE the same as BC?
Yes. They refer to the same years. 400 BC and 400 BCE are the same year.
Why is there no year zero?
Years before 1 were counted backwards from 1 without a zero in the system Bede popularised, so 1 BC is followed directly by AD 1.
Which should I use for school work?
Follow your teacher or exam board. Both are correct and mean the same dates.
Sources
- Common Era, Wikipedia.
- Every figure from our own map is worked out from the datasets on the data sources page (checked against Ancient World Mapping Center outlines and Pleiades).