1751

1751 (MDCCLI) was a common year starting on Friday of the Gregorian calendar and a common year starting on Tuesday of the Julian calendar, the 1751st year of the Common Era (CE) and Anno Domini (AD) designations, the 751st year of the 2nd millennium, the 51st year of the 18th century, and the 2nd year of the 1750s decade.

As of the start of 1751, the Gregorian calendar was 11 days ahead of the Julian calendar, which remained in localized use until 1923.

In Britain and its colonies (except Scotland),[a] 1751 only had 282 days due to the Calendar (New Style) Act 1750, which ended the year on 31 December (rather than nearly three months later according to its previous rule).

The Encyclopédie is first published.