Most people sleep in beds of some sort. Others don't, but they still sleep lying down. Some people sleep sitting... and then there are those who can, somehow, fall asleep while standing upright. They don't slump over in their sleep. They're still standing even while zonked out.
This usually comes in two types: a character is so much of a Sleepyhead that they can fall asleep even standing, or a character is so exhausted that they fall asleep while standing.
A frequent sign of a Sleepyhead or Heavy Sleeper is their ability to remain asleep standing up even while sleeping. This character has been known to fall asleep while standing up, usually on multiple occasions. This is usually Played for Laughs. But, a character that is so exhausted they don't have time to lay down is more likely to be Played for Drama (though it's still often played for comedy).
- In Naruto, Rock Lee, after being completely and mercilessly thrashed by Gaara, pushing his body way past its limits, and suffering permanent damage to two limbs and his spine, manages to stand back up despite being unconscious at the time, presumably by sheer willpower.
- One Piece: Luffy, being a Sleepyhead, can sometimes sleep while standing right up. As shown with his grandpa Garp, this apparently runs in the family.
- On Pokémon, Psyduck falls asleep both standing up and with its eyes open after listening to the lullaby sung by Jigglypuff.
- In Pokémon Reset Bloodlines, Erika is explicitly narcoleptic and is known to pass out even while standing.
- In Control, Yukari causes a scandal during her first year of high school when she splashed the vice principal with water. What actually occured was she was made to hold water in the hallway, but she fell asleep standing up. The vice principal noticed her and accidentally spooked her awake. Yukari accidentally splashed him with water when she awoke.
- In Animorphs the centauroid Andalites sleep standing up, and with one of their secondary eyes open.
- In the Sword of Truth series, one villain fell asleep standing while a captive of Mord-Sith, who love using Sleep Deprivation Punishment.
- In Gorky Park, when conducting an investigation at Moscow's Kazan Station, Arkady Renko encounters this trope when he sees "Soldiers leaned slackly against the wall in a sleep so tangibly deep that the heroic mosaics of the ceiling overhead could have been their communal dream."
- This is mentioned in Night Watch as a skill Vimes has developed over thirty years of being a watchman, though he notes that it's a fairly poor replacement for an actual proper sleep and you shouldn't try to do it for more than a few nights in a row.
- One episode of Cheers had Woody not only fall asleep while standing up, but while his eyes were still open.
- The New Avengers has one episode where the heroes witness the British Army's newest anti-terrorist weapon: an air-dropped knock-out gas that causes loss of consciousness, but has no other detrimental effects. Criminals steal a tanker truck of the stuff, and dose a large suburb of London with it, intending to rob the locale blind. The Avengers, being immunized during the test, are unaffected. John Steed notes, however, that one bobby (British uniformed policeman) is dozing upright at his post, and comments, "They really do sleep standing up!"
- Zigzagged for the Borg (a race of emotionless cyborgs) and a few ex-Borg like Seven of Nine in the Star Trek series. While they do not sleep per se, they "regenerate" standing up in alcoves. Regeneration is similar to sleep (they even dream while regenerating), but it also helps to repair damage to some extent, which is why Seven often regenerates for days at a time after being damaged.
- One episode of El Chavo del ocho has Chavo doing this because he couldn't sleep last night, he fell asleep while having a conversation with Quico, and later, with Don Ramón.
- Jeff and/or Lachy from The Wiggles are prime examples of this trope.
- Pokémon: Ojou Erika is constantly falling asleep for no clear reason. This dates back to Pokémon Red and Blue. where she falls asleep mid-sentence while sitting down. It's most pronounced in the remake Pokémon Let's Go, Pikachu! and Let's Go, Eevee!, where upon challenging Erika she'll doze off mid-sentence, still standing up at that. The most popular fan theories are that either spending a lot of time time around Grass-type Pokémon who know Sleep Powder is to blame or Erika is narcoleptic.
- Animal Crossing:
- In the N64 title and its Gamecube ports, villagers can often be found asleep outside their houses late at night or early in the morning. To make it more embarrassing, they fall asleep standing up.
- In New Leaf, sometimes villagers are sleeping when you enter their house. That's all fine and dandy, except for the fact they fell asleep while standing.
- Fate/Grand Order:
- A common gag involving Tristan is that, due to him having his Eyes Always Shut, it's hard to tell whether he's currently awake or sleeping - and he does go sleeping quite a few times, even while standing.
- Okita Alter has a tendency to doze off during her skill activation animation, only to insist that she wasn't and that she was awake moments later.
- In Tiny Toon Adventures: Buster's Hidden Treasure, as part of Buster's Idle Animation, if you leave Buster alone long enough, he will fall asleep standing up.
- The King of Fighters: In older games, K' has an Idle Animation where he slowly and surely goes asleep while standing up. He's simply bored with the prospect of fighting in the KOF tournaments.
- Starbound: Tonouac, the caretaker of the Sovereign Temple, will fall asleep standing after giving the PC a very short tour, apparently due to the excitement of finally having a visitor. (The temple is one of the holiest places of the Kluex faith and is extremely restricted. There's not even any other clergy besides him.)
- My Little Pony: Friendship Is Magic: This appears as a Furry Reminder when an exhausted Shining Armor falls asleep while standing.
- The third episode of Josie and the Pussycats In Outer Space has the group visit a planet where a city's inhabitants are all asleep, nearly all them standing upright. One is even bent over a water fountain, getting splashed in the face, snoring obliviously. This was the result of "purple dust," a powdered sedative delivered by The Villain's allies as part of his Evil Plan.
- Zero in Numberjacks falls asleep a lot because he's essentially a baby. He's nearly always upright before falling asleep, although sometimes he will lie down just before falling asleep.
- In Tom and Jerry episode "Sleepy-Time Tom" (1951), Tom is found by his owner sleeping like this after a long night out with his pals.
- Having spent a week helping Kiki with her recurring nightmare, Steven in the Steven Universe episode "Kiki's Pizza Delivery Service" ends up falling asleep while standing next to Jenny.
- Many animals, especially prey animals, can do this. It's advantageous to survival to be quick on your feet, even during rest. Horses are the most famous example but, contrary to popular belief, horses only nap standing up; they can't enter REM sleep unless they're laying down.
- Various military authors, both factual and in embellished fiction, have said that if exhausted enough, it is possible for a soldier to fall asleep while marching. This might be an Urban Legend but these tales have been related at least since the Napoleonic Wars, and WW2-based fiction by people like Sven Hassel, or Embellished Autbiography by Guy Sajer, contend this is true. In one of Hassel's novels, the theory is that it is a sort of enhanced self-hypnosis in action.
- This trope sometimes led to gruesome accidents in the Industrial Revolution, long before any sort of workplace safety protocols were established. Men and women often worked fourteen- or sixteen-hour shifts standing up manning heavy machinery, and would topple into them as they fell asleep.
- Very much a true trope in the military, due to sometimes erratic and/or inadequate sleep schedules where someone standing watch can pass out on their feet. It also tends to elicit more empathy in others if noticed, leading to a wake up rather than being written up.