The identity of the youngest world record holder depends on the specific world record in question. There are many world records in various categories, including sports, music, academics, and more.

That being said, one example of a young world record holder is Aryan Mishra, who in 2020 became the youngest person to achieve the rank of Grandmaster in chess, at the age of 12 years, 4 months, and 25 days. Another example is Alia Sabur, who in 2008 became the youngest person to receive a PhD, at the age of 19 years and 257 days, according to Guinness World Records.
However, it’s worth noting that world records are constantly being broken and updated, so the answer to this question may change over time.