AD 666

Millennium: 1st millennium
Centuries:
Decades:
Years:
666 in various calendars
Gregorian calendar666
DCLXVI
Ab urbe condita1419
Armenian calendar115
ԹՎ ՃԺԵ
Assyrian calendar5416
Balinese saka calendar587–588
Bengali calendar73
Berber calendar1616
Buddhist calendar1210
Burmese calendar28
Byzantine calendar6174–6175
Chinese calendar乙丑年 (Wood Ox)
3363 or 3156
    — to —
丙寅年 (Fire Tiger)
3364 or 3157
Coptic calendar382–383
Discordian calendar1832
Ethiopian calendar658–659
Hebrew calendar4426–4427
Hindu calendars
 - Vikram Samvat722–723
 - Shaka Samvat587–588
 - Kali Yuga3766–3767
Holocene calendar10666
Iranian calendar44–45
Islamic calendar45–46
Japanese calendarHakuchi 17
(白雉17年)
Javanese calendar557–558
Julian calendar666
DCLXVI
Korean calendar2999
Minguo calendar1246 before ROC
民前1246年
Nanakshahi calendar−802
Seleucid era977/978 AG
Thai solar calendar1208–1209
Tibetan calendar阴木牛年
(female Wood-Ox)
792 or 411 or −361
    — to —
阳火虎年
(male Fire-Tiger)
793 or 412 or −360
Barking Abbey: curfew tower (east London)

Year 666 (DCLXVI) was a common year starting on Thursday (link will display the full calendar) of the Julian calendar. The denomination 666 for this year has been used since the early medieval period, when the Anno Domini calendar era became the prevalent method in Europe for naming years.