How Long Can You Actually Go Without Sleep?

Whether you’re planning an all-nighter or dealing with insomnia, read on to learn how your body will handle sleepless days and nights.

Sleepless nights are a reality for many of us: parents of newborns, students cramming for tests, people struggling with insomnia. We all know that we need to sleep, but come on, can’t we go without it for a while? Sort of, but it’s not pretty. 

The world records for sleep deprivation

The most famous record holder for sleep deprivation—although he doesn’t hold the current record— is Randy Gardner, who is widely considered to have undergone the best-documented period of extreme sleep deprivation by a human: 264 hours, or about 11 days. 

As NPR reports, Gardner was working on a science fair project with two other students in 1963, and they decided to beat the 260 sleepless hours that they heard a radio DJ had accomplished. Gardner lost the coin toss, and he went without sleep while the others monitored him and tested his cognition. He was 17 at the time.

His experiment gained media attention, and soon Stanford sleep researcher William Dement and Navy medic John Ross began evaluating him as well. After the 264-hour mark was reached, Gardner underwent a brain scan (showing him to be healthy) and then slept for 14 hours. 

His record was broken multiple times after that, most recently in 1986, with a nearly 19-day sleepless stretch by stuntman Robert McDonald. That’s the last documented world record. Don’t try to beat it, though: the Guinness Book of World Records decided in 1997 to “stop monitoring” the sleeplessness record. They recognize that publishing a record means that people will keep trying to beat it, and the effects of extreme sleep deprivation are considered dangerous enough that they didn't want to encourage it.

That said, if you’d like to read more about the record holders and what their experiences were like, Guinness has a rundown on their website. Of note is that Peter Tripp, a DJ who competed for the record in the 1950s, experienced extreme hallucinations that may have been due to the Ritalin he took to stay awake, rather than as a direct effect of sleeplessness. (That said, hallucinations of some kind may still occur from sleep deprivation alone.) 

The effects of extreme sleep deprivation

The record holders from the Guinness site often reported feeling nauseous and irritable. By day four, one of the scientists observing Gardner recalled that he had “hallucinations, delusions, and an extremely short attention span.” 

1974 record breaker Roger Guy English, who used no stimulants besides caffeine, reported experiencing hallucinations that lasted even when the experiment was over. Another record breaker, Maureen Weston, had hallucinations while she was sleep-deprived, but said that she fully recovered once she was able to get some sleep. 

A StatPearls guide to sleep deprivation reports that chronic sleep loss (which can include some sleep, but not enough, over a longer period of time) can lead to “increased mortality and morbidity, poor performance on waking activities resulting in increased accidents and injuries, lower self-reported quality of life, decreased family well-being, and reduced use of health care.” They add: “It is clear that sleep loss has a profound effect on human health and well-being.” 

How long can the average person go without sleep? 

For practical advice, let’s turn to the military. The military needs its members to function, but often gives them assignments that make sleep difficult or impossible, so they’ve developed policies on the issue. A Pentagon report on sleep deprivation defines “total sleep deprivation” as 24 hours awake, or skipping your normal sleeping window, whenever that might be. In other words, if you normally wake up at 7 a.m. but stayed up all night playing video games (or getting shot at by the enemy), when 7 a.m. rolls around again, you would be considered to be in a state of total sleep deprivation. 

They also consider “partial sleep deprivation” to mean a time period in which you’re getting less than seven hours of sleep each night, because your sleep period was either shortened or interrupted. One week of this is considered “chronic partial sleep deprivation.” 

According to the same report, each 24 hours of total sleep deprivation comes with an estimated “25-35% degradation of cognitive task performance.” It’s not that you hit a wall at a specific number of hours and become unable to function, but rather that, over the time you are sleep deprived, ur brain work less & les gud.

The report also cites findings that sleep deprivation can increase the risk of traumatic brain injury, increases feelings of emotional exhaustion and “role overload” (burnout), increases and worsens anxiety symptoms, exacerbates symptoms of PTSD, and increases depressive symptoms and suicidal ideation and attempts. 

The bottom line, according to the military: members should be given duties that allow eight hours of sleep out of every 24 hours, if possible. Where that’s not possible, plan on “banking” sleep ahead of that sleepless time, and allowing time for “recovery” sleep afterward (like how Gardner zonked out for 14 hours following his experiment).

What if I can’t sleep? 

A clinical case of insomnia is a different situation than a student or soldier pulling an all-nighter. Insomnia can have many causes, and it’s worth getting evaluated to find out what’s going on in your body and brain that is stopping you from getting a good night’s sleep. The advice you get will depend on exactly what is wrong. 

It’s worth mentioning, though, that just because you think you’re not sleeping doesn’t mean you’ve actually had a sleepless night. Anytime I interview a sleep expert, they always have stories about patients who swore up and down they didn’t sleep at all, but a sleep study showed them catching a few Z’s without realizing they had drifted off. 

Even the Guinness book recognizes this: one of the reasons they stopped keeping sleeplessness records, besides the health risk, is that people who seem to be awake may still be experiencing “microsleeps.” The CDC, in discussing the effects of long shifts on nurses, writes that “a sleep-deprived person cannot control the onset of microsleeps and often is unaware that they are occurring.” 

Sleep specialists recommend that, instead of watching the clock and worrying about how much sleep you’re not getting, do your best to relax. Relaxation is almost as good as sleep, and often turns out to lead to sleep. If you still notice problems with daytime sleepiness, or if you have other concerns about your sleep, see a doctor.