<P> This is a list of Presidents of the United States by time in office . The basis of the list is the difference between dates; if counted by number of calendar days all the figures would be one greater, with the exception of Grover Cleveland, who would receive two days . </P> <P> Since 1789, there have been 44 people sworn into office as President of the United States, and 45 presidencies, as Grover Cleveland served two non-consecutive terms and is counted chronologically as both the 22nd and 24th president . Of the individuals elected president, four (William Henry Harrison, Zachary Taylor, Warren G. Harding, and Franklin D. Roosevelt) died of natural causes while in office, four (Abraham Lincoln, James A. Garfield, William McKinley, and John F. Kennedy) were assassinated, and one (Richard Nixon) resigned . </P> <P> William Henry Harrison spent the shortest time in office, and Franklin D. Roosevelt spent the longest . He is the only president to have served more than two terms . Presidents since Dwight D. Eisenhower have been constitutionally limited to two terms under the 22nd Amendment . </P> <P> For the incumbent, this list is accurate as of October 10, 2017 . </P>

Who was the president that served 3 terms