| Order | President | Years | Months | Days | Term | Ranking
|
| 40 | Ronald Reagan | 69 | 11 | 14 | January 20, 1981 - January 20, 1989 | 1
|
| 9 | William Henry Harrison | 68 | 0 | 23 | March 4, 1841 - April 4, 1841 | 2
|
| 15 | James Buchanan | 65 | 10 | 9 | March 4, 1857 - March 4, 1861 | 3
|
| 41 | George H. W. Bush | 64 | 7 | 8 | January 20, 1989 - January 20, 1993 | 4
|
| 12 | Zachary Taylor | 64 | 3 | 8 | March 4, 1849 - July 9, 1850 | 5
|
| 34 | Dwight D. Eisenhower | 62 | 3 | 6 | January 20, 1953 - January 20, 1961 | 6
|
| 7 | Andrew Jackson | 61 | 11 | 17 | March 4, 1829 - March 4, 1837 | 7
|
| 2 | John Adams | 61 | 4 | 4 | March 4, 1797 - March 4, 1801 | 8
|
| 38 | Gerald Ford | 61 | 0 | 26 | August 9, 1974 - January 20, 1977 | 9
|
| 33 | Harry S. Truman | 60 | 11 | 4 | April 12, 1945 - January 20, 1953 | 10
|
| 5 | James Monroe | 58 | 10 | 4 | March 4, 1817 - March 4, 1825 | 11
|
| 4 | James Madison | 57 | 11 | 16 | March 4, 1809 - March 4, 1817 | 12
|
| 3 | Thomas Jefferson | 57 | 10 | 19 | March 4, 1801 - March 4, 1809 | 13
|
| 6 | John Quincy Adams | 57 | 7 | 21 | March 4, 1825 - March 4, 1829 | 14
|
| 1 | George Washington | 57 | 2 | 8 | April 30, 1789 - March 4, 1797 | 15
|
| 17 | Andrew Johnson | 56 | 3 | 17 | April 15, 1865 - March 4, 1869 | 16
|
| 28 | Woodrow Wilson | 56 | 2 | 4 | March 4, 1913 - March 4, 1921 | 17
|
| 37 | Richard Nixon | 56 | 0 | 11 | January 20, 1969 - August 9, 1974 | 18
|
| 24 | Grover Cleveland * | 55 | 11 | 14 | March 4, 1893 - March 4, 1897 | 19
|
| 23 | Benjamin Harrison | 55 | 6 | 12 | March 4, 1889 - March 4, 1893 | 20
|
| 29 | Warren Harding | 55 | 4 | 2 | March 4, 1921 - August 2, 1923 | 21
|
| 36 | Lyndon B. Johnson | 55 | 2 | 26 | November 22, 1963 - January 20, 1969 | 22
|
| 31 | Herbert Hoover | 54 | 6 | 22 | March 4, 1929 - March 4, 1933 | 23
|
| 43 | George W. Bush | 54 | 6 | 14 | January 20, 2001 - | 24
|
| 19 | Rutherford B. Hayes | 54 | 5 | 0 | March 4, 1877 - March 4, 1881 | 25
|
| 8 | Martin Van Buren | 54 | 2 | 27 | March 4, 1837 - March 4, 1841 | 26
|
| 25 | William McKinley | 54 | 1 | 4 | March 4, 1897 - September 14, 1901 | 27
|
| 39 | Jimmy Carter | 52 | 3 | 19 | January 20, 1977 - January 20, 1981 | 28
|
| 16 | Abraham Lincoln | 52 | 0 | 20 | March 4, 1861 - April 15, 1865 | 29
|
| 21 | Chester A. Arthur | 51 | 11 | 14 | September 19, 1881 - March 4, 1885 | 30
|
| 27 | William Howard Taft | 51 | 5 | 17 | March 4, 1909 - March 4, 1913 | 31
|
| 32 | Franklin Delano Roosevelt | 51 | 1 | 4 | March 4, 1933 - April 12, 1945 | 32
|
| 30 | Calvin Coolidge | 51 | 0 | 29 | August 2, 1923 - March 4, 1929 | 33
|
| 10 | John Tyler | 51 | 0 | 6 | April 4, 1841 - March 4, 1845 | 34
|
| 13 | Millard Fillmore | 50 | 6 | 2 | July 9, 1850 - March 4, 1853 | 35
|
| 11 | James Knox Polk | 49 | 4 | 2 | March 4, 1845 - March 4, 1849 | 36
|
| 20 | James Garfield | 49 | 3 | 13 | March 4, 1881 - September 19, 1881 | 37
|
| 14 | Franklin Pierce | 48 | 3 | 9 | March 4, 1853 - March 4, 1857 | 38
|
| 22 | Grover Cleveland * | 47 | 11 | 14 | March 4, 1885 - March 4, 1889 | 39
|
| 18 | Ulysses S. Grant | 46 | 10 | 5 | March 4, 1869 - March 4, 1877 | 40
|
| 42 | Bill Clinton | 46 | 5 | 1 | January 20, 1993 - January 20, 2001 | 41
|
| 35 | John F. Kennedy ** | 43 | 7 | 22 | January 20, 1961 - November 22, 1963 | 42
|
| 26 | Theodore Roosevelt ** | 42 | 10 | 18 | September 14, 1901 - March 4, 1909 | 43
|
( * ) Since Grover Cleveland served two non-consecutive terms, his age at ascension each time is represented.
( ** ) Since Theodore Roosevelt finished McKinley's second term, he was not actually elected president until he was over the age of 46. Consequently John F. Kennedy is still the youngest man ever to be elected president.