After the first presidential debate featuring both incumbent U.S. President Joe Biden and his challenger, former President Donald Trump, the topic of Biden's age - currently 81 - has been thrust back into the spotlight. In fact, Biden and Trump were the oldest U.S. presidents ever at the time of their inauguration. Trump was 70 years old in 2017 and Biden was 78 in 2021. Ronald Reagan, who was 69 in 1981, comes third. At the start of a second term, Biden would be 82, making him 86 when reaching his term limit. Trump is now 78 - the same age as Biden when he started his first term - and would be 82 at term limit.
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.
