The youngest person to become President of the United States was Theodore Roosevelt, who assumed office at the age of 42 years and 322 days after the assassination of President William McKinley in 1901
. However, Roosevelt was not elected to his first term at that age; he succeeded to the presidency. The youngest president to be elected was John F. Kennedy, who was inaugurated at 43 years and 236 days old in 1961
. Kennedy remains the youngest person ever elected to the presidency. In summary:
- Youngest president to assume office: Theodore Roosevelt (42 years, 322 days) through succession after McKinley's assassination.
- Youngest president elected: John F. Kennedy (43 years, 236 days).
Both brought youthful energy and left significant impacts on American history
