<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 . Following ratification of the Twenty - second Amendment in 1951, presidents--beginning with Dwight D. Eisenhower--have been ineligible for election to a third term or for election to a second full term after serving more than two years of a term to which some other person was elected president . The amendment contained a grandfather clause that explicitly exempted the incumbent president--then Harry S. Truman--from the new term limitations . </P> <Table> <Tr> <Th> Rank </Th> <Th> President </Th> <Th> Length in days </Th> <Th> Order of presidency </Th> <Th> Number of terms </Th> </Tr> <Tr> <Td> </Td> <Td> Franklin D. Roosevelt </Td> <Td> 7003442200000000000 ♠ 4,422 </Td> <Td> 32nd March 4, 1933--April 12, 1945 </Td> <Td> Three full terms; died 2 months and 23 days into fourth term </Td> </Tr> <Tr> <Td> tie </Td> <Td> Thomas Jefferson </Td> <Td> 7003292200000000000 ♠ 2,922 </Td> <Td> 3rd March 4, 1801--March 4, 1809 </Td> <Td> Two full terms </Td> </Tr> <Tr> <Td> James Madison </Td> <Td> 7003292200000000000 ♠ 2,922 </Td> <Td> 4th March 4, 1809--March 4, 1817 </Td> <Td> Two full terms </Td> </Tr> <Tr> <Td> James Monroe </Td> <Td> 7003292200000000000 ♠ 2,922 </Td> <Td> 5th March 4, 1817--March 4, 1825 </Td> <Td> Two full terms </Td> </Tr> <Tr> <Td> Andrew Jackson </Td> <Td> 7003292200000000000 ♠ 2,922 </Td> <Td> 7th March 4, 1829--March 4, 1837 </Td> <Td> Two full terms </Td> </Tr> <Tr> <Td> Ulysses S. Grant </Td> <Td> 7003292200000000000 ♠ 2,922 </Td> <Td> 18th March 4, 1869--March 4, 1877 </Td> <Td> Two full terms </Td> </Tr> <Tr> <Td> Grover Cleveland </Td> <Td> 2,922 </Td> <Td> 22nd March 4, 1885--March 4, 1889 </Td> <Td> Two full terms (non-consecutive) </Td> </Tr> <Tr> <Td> 24th March 4, 1893--March 4, 1897 </Td> </Tr> <Tr> <Td> Woodrow Wilson </Td> <Td> 7003292200000000000 ♠ 2,922 </Td> <Td> 28th March 4, 1913--March 4, 1921 </Td> <Td> Two full terms </Td> </Tr> <Tr> <Td> Dwight D. Eisenhower </Td> <Td> 7003292200000000000 ♠ 2,922 </Td> <Td> 34th January 20, 1953--January 20, 1961 </Td> <Td> Two full terms </Td> </Tr> <Tr> <Td> Ronald Reagan </Td> <Td> 7003292200000000000 ♠ 2,922 </Td> <Td> 40th January 20, 1981--January 20, 1989 </Td> <Td> Two full terms </Td> </Tr> <Tr> <Td> Bill Clinton </Td> <Td> 7003292200000000000 ♠ 2,922 </Td> <Td> 42nd January 20, 1993--January 20, 2001 </Td> <Td> Two full terms </Td> </Tr> <Tr> <Td> George W. Bush </Td> <Td> 7003292200000000000 ♠ 2,922 </Td> <Td> 43rd January 20, 2001--January 20, 2009 </Td> <Td> Two full terms </Td> </Tr> <Tr> <Td> Barack Obama </Td> <Td> 7003292200000000000 ♠ 2,922 </Td> <Td> 44th January 20, 2009--January 20, 2017 </Td> <Td> Two full terms </Td> </Tr> <Tr> <Td> 14 </Td> <Td> George Washington </Td> <Td> 7003286500000000000 ♠ 2,865 </Td> <Td> 1st April 30, 1789--March 4, 1797 </Td> <Td> Two full terms </Td> </Tr> <Tr> <Td> 15 </Td> <Td> Harry S. Truman </Td> <Td> 7003284000000000000 ♠ 2,840 </Td> <Td> 33rd April 12, 1945--January 20, 1953 </Td> <Td> One partial term (3 years, 9 months, and 8 days), followed by one full term </Td> </Tr> <Tr> <Td> 16 </Td> <Td> Theodore Roosevelt </Td> <Td> 7003272800000000000 ♠ 2,728 </Td> <Td> 26th September 14, 1901--March 4, 1909 </Td> <Td> One partial term (3 years, 5 months, and 18 days), followed by one full term </Td> </Tr> <Tr> <Td> 17 </Td> <Td> Calvin Coolidge </Td> <Td> 7003204100000000000 ♠ 2,041 </Td> <Td> 30th August 2, 1923--March 4, 1929 </Td> <Td> One partial term (1 year, 7 months, and 2 days), followed by one full term </Td> </Tr> <Tr> <Td> 18 </Td> <Td> Richard Nixon </Td> <Td> 7003202700000000000 ♠ 2,027 </Td> <Td> 37th January 20, 1969--August 9, 1974 </Td> <Td> One full term; resigned 1 year, 6 months, and 20 days into second term </Td> </Tr> <Tr> <Td> 19 </Td> <Td> Lyndon B. Johnson </Td> <Td> 7003188600000000000 ♠ 1,886 </Td> <Td> 36th November 22, 1963--January 20, 1969 </Td> <Td> One partial term (1 year, 1 month, and 29 days), followed by one full term </Td> </Tr> <Tr> <Td> 20 </Td> <Td> William McKinley </Td> <Td> 7003165400000000000 ♠ 1,654 </Td> <Td> 25th March 4, 1897--September 14, 1901 </Td> <Td> One full term; assassinated 6 months and 2 days into second term, dying 8 days later, 6 months and 10 days into that term </Td> </Tr> <Tr> <Td> 21 </Td> <Td> Abraham Lincoln </Td> <Td> 7003150300000000000 ♠ 1,503 </Td> <Td> 16th March 4, 1861--April 15, 1865 </Td> <Td> One full term; assassinated 1 month and 10 days into second term, dying 1 day later, 1 month and 11 days into that term </Td> </Tr> <Tr> <Td> 22 tie </Td> <Td> John Quincy Adams </Td> <Td> 7003146100000000000 ♠ 1,461 </Td> <Td> 6th March 4, 1825--March 4, 1829 </Td> <Td> One full term </Td> </Tr> <Tr> <Td> Martin Van Buren </Td> <Td> 7003146100000000000 ♠ 1,461 </Td> <Td> 8th March 4, 1837--March 4, 1841 </Td> <Td> One full term </Td> </Tr> <Tr> <Td> James K. Polk </Td> <Td> 7003146100000000000 ♠ 1,461 </Td> <Td> 11th March 4, 1845--March 4, 1849 </Td> <Td> One full term </Td> </Tr> <Tr> <Td> Franklin Pierce </Td> <Td> 7003146100000000000 ♠ 1,461 </Td> <Td> 14th March 4, 1853--March 4, 1857 </Td> <Td> One full term </Td> </Tr> <Tr> <Td> James Buchanan </Td> <Td> 7003146100000000000 ♠ 1,461 </Td> <Td> 15th March 4, 1857--March 4, 1861 </Td> <Td> One full term </Td> </Tr> <Tr> <Td> Rutherford B. Hayes </Td> <Td> 7003146100000000000 ♠ 1,461 </Td> <Td> 19th March 4, 1877--March 4, 1881 </Td> <Td> One full term </Td> </Tr> <Tr> <Td> Benjamin Harrison </Td> <Td> 7003146100000000000 ♠ 1,461 </Td> <Td> 23rd March 4, 1889--March 4, 1893 </Td> <Td> One full term </Td> </Tr> <Tr> <Td> William Howard Taft </Td> <Td> 7003146100000000000 ♠ 1,461 </Td> <Td> 27th March 4, 1909--March 4, 1913 </Td> <Td> One full term </Td> </Tr> <Tr> <Td> Herbert Hoover </Td> <Td> 7003146100000000000 ♠ 1,461 </Td> <Td> 31st March 4, 1929--March 4, 1933 </Td> <Td> One full term </Td> </Tr> <Tr> <Td> Jimmy Carter </Td> <Td> 7003146100000000000 ♠ 1,461 </Td> <Td> 39th January 20, 1977--January 20, 1981 </Td> <Td> One full term </Td> </Tr> <Tr> <Td> George H.W. Bush </Td> <Td> 7003146100000000000 ♠ 1,461 </Td> <Td> 41st January 20, 1989--January 20, 1993 </Td> <Td> One full term </Td> </Tr> <Tr> <Td> 33 </Td> <Td> John Adams </Td> <Td> 7003146000000000000 ♠ 1,460 </Td> <Td> 2nd March 4, 1797--March 4, 1801 </Td> <Td> One full term </Td> </Tr> <Tr> <Td> 34 </Td> <Td> John Tyler </Td> <Td> 7003143000000000000 ♠ 1,430 </Td> <Td> 10th April 4, 1841--March 4, 1845 </Td> <Td> One partial term (3 years and 11 months) </Td> </Tr> <Tr> <Td> 35 </Td> <Td> Andrew Johnson </Td> <Td> 7003141900000000000 ♠ 1,419 </Td> <Td> 17th April 15, 1865--March 4, 1869 </Td> <Td> One partial term (3 years, 10 months, and 17 days) </Td> </Tr> <Tr> <Td> 36 </Td> <Td> Chester A. Arthur </Td> <Td> 7003126200000000000 ♠ 1,262 </Td> <Td> 21st September 19, 1881--March 4, 1885 </Td> <Td> One partial term (3 years, 5 months, and 13 days) </Td> </Tr> <Tr> <Td> 37 </Td> <Td> John F. Kennedy </Td> <Td> 7003103600000000000 ♠ 1,036 </Td> <Td> 35th January 20, 1961--November 22, 1963 </Td> <Td> Assassinated 2 years, 10 months, and 2 days into term </Td> </Tr> <Tr> <Td> 38 </Td> <Td> Millard Fillmore </Td> <Td> 7002969000000000000 ♠ 969 </Td> <Td> 13th July 9, 1850--March 4, 1853 </Td> <Td> One partial term (2 years, 7 months, and 23 days) </Td> </Tr> <Tr> <Td> 39 </Td> <Td> Gerald Ford </Td> <Td> 7002895000000000000 ♠ 895 </Td> <Td> 38th August 9, 1974--January 20, 1977 </Td> <Td> One partial term (2 years, 5 months, and 11 days) </Td> </Tr> <Tr> <Td> 40 </Td> <Td> Warren G. Harding </Td> <Td> 7002881000000000000 ♠ 881 </Td> <Td> 29th March 4, 1921--August 2, 1923 </Td> <Td> Died 2 years, 4 months, and 29 days into term </Td> </Tr> <Tr> <Td> 41 </Td> <Td> Donald Trump </Td> <Td> 7002644000000000000 ♠ 644 </Td> <Td> 45th January 20, 2017--Incumbent </Td> <Td> Serving first term </Td> </Tr> <Tr> <Td> 42 </Td> <Td> Zachary Taylor </Td> <Td> 7002492000000000000 ♠ 492 </Td> <Td> 12th March 4, 1849--July 9, 1850 </Td> <Td> Died 1 year, 4 months, and 5 days into term </Td> </Tr> <Tr> <Td> 43 </Td> <Td> James A. Garfield </Td> <Td> 7002199000000000000 ♠ 199 </Td> <Td> 20th March 4, 1881--September 19, 1881 </Td> <Td> Assassinated 3 months and 28 days into term, dying 79 days later, 6 months and 15 days into term </Td> </Tr> <Tr> <Td> 44 </Td> <Td> William Henry Harrison </Td> <Td> 7001310000000000000 ♠ 31 </Td> <Td> 9th March 4, 1841--April 4, 1841 </Td> <Td> Died 31 days into term </Td> </Tr> </Table>

Who had the longest tenure as president of usa