1683 (MDCLXXXIII) was a common year starting on Friday of the Gregorian calendar and a common year starting on Monday of the Julian calendar, the 1683rd year of the Common Era (CE) and Anno Domini (AD) designations, the 683rd year of the 2nd millennium, the 83rd year of the 17th century, and the 4th year of the 1680s decade. As of the start of 1683, the Gregorian calendar was 10 days ahead of the Julian calendar, which remained in localized use until 1923.