1888 (MDCCCLXXXVIII) was a leap year starting on Sunday of the Gregorian calendar and a leap year starting on Friday of the Julian calendar, the 1888th year of the Common Era (CE) and Anno Domini (AD) designations, the 888th year of the 2nd millennium, the 88th year of the 19th century, and the 9th year of the 1880s decade. As of the start of 1888, the Gregorian calendar was 12 days ahead of the Julian calendar, which remained in localized use until 1923.
