> Randy Gardner (born August 7, 1949) is the holder of the scientifically documented record for the longest a human has intentionally gone without sleep not using stimulants of any kind. In 1964, Gardner, a high school student in San Diego, California, stayed awake for 264.4 hours (11 days 25 minutes).

https://en.wikipedia.org/wiki/Randy_Gardner_(record_holder)

The article mentions longer records but they aren't so well documented.