President-elect Joe Biden is celebrating his 78th birthday today. When the 46th president will be inaugurated in January, that will make him the oldest president in U.S. history. His predecessor Donald Trump had also been the oldest president to ever take office at his inauguration four years ago (he was 70 at the time).
But taking a look at all presidents’ ages at the time of their inauguration since 1789, no clear trend is visible. Before Trump and Biden, presidents’ ages were actually well below average. Barack Obama took office at 47 years and 169 days, according to Potus.com, making him the fifth youngest president at the time of inauguration. Bill Clinton, who was 46 when he took over, was the third youngest - only John F. Kennedy (43) and Teddy Roosevelt (42) were younger.
Some of the oldest presidents hail from past centuries. William Henry Harrison was 68 at his inauguration in 1841 (he died a month later of typhoid and pneumonia), making him the fourth-oldest president ever. James Buchanan, who took office in 1857, was the fifth-oldest president at 65.