2013 (twenty thirteen or two thousand thirteen) (MMXIII) was a common year starting on Tuesday of the Gregorian calendar, the 2013th year of the Common Era (CE) and Anno Domini (AD) designations, the 13th year of the 3rd millennium, the 13th year of the 21st century, and the 4th year of the 2010s decade. It was the first year since 1987 to have all four of its digits being different numbers.