List of presidents of the United States by age
The median age upon accession to the presidency is 55 years and 3 months. This is how old Lyndon B. Johnson was at the time of his inauguration. The youngest person to assume the office was Theodore Roosevelt, who became president at the age of , following William McKinley's assassination; the oldest was Donald Trump, who was old at his inauguration. The youngest person to be elected president was John F. Kennedy, at of age on election day; the oldest was Ronald Reagan, who was old at the time of his election to a second term.
1864 Democratic National Convention
The Convention nominated Major General George B. McClellan from New Jersey for President, and Representative George H. Pendleton of Ohio for Vice President. McClellan, age 37 at the time of the convention and Pendleton, age 39, are the youngest presidential ticket ever nominated as of 2016.