Longest I stayed up was about 50 hours. I was just completely zombied for most of that time. When I finally got to sleep, I slept for 20 hours.

My sleep schedule currently is a disaster, though. Since I'm a total NEET/hikkomori/other weeaboo words, my sleep has nothing to sync to, and it doesn't naturally sync to the day/night cycle, which has kinda been a problem for my entire life, it just used to sync to school or something. But if I ever had a break from school, it would drift in and out of phase of the normal cycle, as if it has a lower frequency (longer period). I haven't done much observation or data gathering, since it's too inconsistent to be conclusive, but I'd say it's about 25-26 hours. sometimes more, sometimes less.

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