1731

Millennium: 2nd millennium
Centuries:
Decades:
Years:
1731: John Bevis becomes first Earth astronomer to observe the Crab Nebula.
1731 in various calendars
Gregorian calendar1731
MDCCXXXI
Ab urbe condita2484
Armenian calendar1180
ԹՎ ՌՃՁ
Assyrian calendar6481
Balinese saka calendar1652–1653
Bengali calendar1138
Berber calendar2681
British Regnal yearGeo. 2 – 5 Geo. 2
Buddhist calendar2275
Burmese calendar1093
Byzantine calendar7239–7240
Chinese calendar庚戌年 (Metal Dog)
4428 or 4221
    — to —
辛亥年 (Metal Pig)
4429 or 4222
Coptic calendar1447–1448
Discordian calendar2897
Ethiopian calendar1723–1724
Hebrew calendar5491–5492
Hindu calendars
 - Vikram Samvat1787–1788
 - Shaka Samvat1652–1653
 - Kali Yuga4831–4832
Holocene calendar11731
Igbo calendar731–732
Iranian calendar1109–1110
Islamic calendar1143–1144
Japanese calendarKyōhō 16
(享保16年)
Javanese calendar1655–1656
Julian calendarGregorian minus 11 days
Korean calendar4064
Minguo calendar181 before ROC
民前181年
Nanakshahi calendar263
Thai solar calendar2273–2274
Tibetan calendar阳金狗年
(male Iron-Dog)
1857 or 1476 or 704
    — to —
阴金猪年
(female Iron-Pig)
1858 or 1477 or 705

1731 (MDCCXXXI) was a common year starting on Monday of the Gregorian calendar and a common year starting on Friday of the Julian calendar, the 1731st year of the Common Era (CE) and Anno Domini (AD) designations, the 731st year of the 2nd millennium, the 31st year of the 18th century, and the 2nd year of the 1730s decade. As of the start of 1731, the Gregorian calendar was 11 days ahead of the Julian calendar, which remained in localized use until 1923.