Cold Equations run in Anime and Manga.
- Attack on Titan:
- Humanity's attempt at reclaiming Wall Maria by sending out 250,000 drafted citizens, many of whom came from the recently-fallen ward of Shiganshina, was done knowing that the operation would likely fail so that humanity would not starve from overpopulation.
- Jean also performs one during the Battle of Trost, using several cornered comrades as a distraction so that the rest of the soldiers following him may escape safely.Marco: I want you to listen to me without getting angry. You're not strong, Jean. That's why you understand how the weak feel. And you're adept at properly assessing a situation, so you know exactly what has to be done at any given time.
- A Certain Magical Index: The New Testament novels introduce Kakeru Kamisato, a reluctant hero. Whenever a disaster happens, he only saves one or a few, almost always pretty girls, and leaves the rest to die. He cynically says trying to save everyone is utter foolishness and will only lead to everyone getting killed. However, when Touma Kamijou consistently manages to save everybody by never giving up and using methods Kakeru never though of, Kakeru eventually admits he was wrong.
- Dragon Ball Super: Broly: When Broly, Paragus, and Beets were stranded on Planet Vampa due to a broken spaceship, Paragus coldly murdered Beets so that their food would last longer.
- Fate/Grand Carnival: Parodied when Ritsuka is informed that Chaldea has too many Servants and it is straining resources. Rather than accept a dock in pay to support them, she puts her Servants in a tournament where the losers are killed, and before the tournament even starts, she eliminates all the 3 Star or less Servants, plus all incarnations of Cu Chulainn.
- Fate/Zero: Towards the end of the Fourth Grail War, Kiritsugu Emiya — a cynical and pragmatic assassin — is doused in Grail Mud and comes into contact with Aŋra Mainiiu, who asks him a series of philosophical questions wherein Kiritsugu must choose between two groups of people, one of which is slightly larger than the other, and the group he chooses to save is divided before the experiment repeats. Kiritsugu consistently chooses the larger number of people in accordance with his Well-Intentioned Extremist philosophy, only for Aŋra Mainiiu to mockingly point out that in the end he's killed far more people than he saved.
- Played for Laughs in Full Metal Panic? Fumoffu. A viral agent is released in the school resulting in Crowd Panic until Kaname dresses down the class. Everyone starts hugging each other, determined to Face Death with Dignity... until Sousake reveals he has enough vaccine for one person. Hilarity Ensues with send-ups of the requisite Lottery of Doom, Heroic Sacrifice and Must Not Die a Virgin tropes. And then they discover that the virus only eats clothing.
- The reason for a series of murders in The Kindaichi Case Files. The victims are all survivors of a crashed ship, with the same initials. One of them had worked out this equation and pushed a girl off who was trying to climb aboard a full lifeboat; in falling, she managed to grab their keychain with their initials.
- Lampshaded in the Martian Successor Nadesico episode "The Lukewarm 'Cold Equation'", where Anti-Hero Akito gets stranded without fuel after piloting his Humongous Mecha out of range of the Cool Starship, and the two leading contenders in the Love Dodecahedron get stranded with him when their rescue attempts fail due to enemy attacks. Akito ejects the mecha's limbs to get it moving, but the oxygen issue comes up again. Akito finally decides to Take a Third Option before they discover that they'd drifted back in range of their starship.
- Planetes:
- Subverted when the exact situation comes up. The testees are placed in a situation where they do not have enough oxygen to outlast the test, either they give up or kill someone to preserve the oxygen they have. Instead, they lower the temperature of the room to reduce their metabolism and oxygen consumption.
- Also Love Freak, Wide-Eyed Idealist Ai debating whether to steal a terrorists' air tank to save herself. Ultimately, is unable to bring herself to steal the air tank and begins suffocating. She suffers enough neurological damage from the oxygen-deprivation before they're rescued that she is left in a wheelchair, though it's suggested that she may recover with time and physical therapy.
- Pokémon 2000: Lugia carries Ash, Pikachu, and the Team Rocket trio to safety from the Legendary Birds, but their combined weight is slowing Lugia down. Realizing that if nothing is done, then they'll all die, Team Rocket jumps off Lugia into the sea, fully expecting to die. Of course, they survive.
- In the second season of Vandread, The Stoic Meia has to take care of Ezra's baby daughter when a space battle breaks out and in the confusion, they accidentally launch in an escape pod. When oxygen begins to run out, Meia has no choice but to throw herself out of the airlock with a smile to make sure Karu lasts until the pod is picked up by Nirvana. It turns out, the pod has just been picked up, and Meia didn't notice until she walked out.
- A variation of this comes up in an episode of Yu-Gi-Oh!. Grandpa tells the main protagonists - via flashback - how he and his colleague Arthur were on an archaeology dig when a cave-in trapped them in an isolated pocket, separated from the others, with limited supplies. Eventually, they decided to play cards to pass the time, and Solomon suggested wagering the last of the water, knowing that there wasn't enough to share, and without it, one of them might die of thirst before they were rescued - if they ever were. Eventually, Solomon realized Arthur was about to pass out from fatigue, and forfeited the game in order to give it to him, even though he could have won on his next move. Fortunate, too, as the rescue team found them soon after.
- Yu-Gi-Oh! GX: When Austin O'Brien was a child, his parents were knocked out when their van crashed in the jungle and caught fire. Austin was struck with indecision on who to save, but ultimately decided to save his father, reasoning that since his father was an expert mercenary that they would have a higher chance of survival in the wilderness together. Fortunately, his father woke up and was able to save his mother before the van exploded. Afterwards, Austin was filled with self-loathing over the fact that if it wasn't for that stroke of luck, he basically condemned his mother to death. When Austin duels Trueman, Trueman reads his mind and taunts him about his past decision. Trueman forces him to relive his trauma by playing a card called The Unchosen One, which forces the opponent to pick one Monster they control and the others get destroyed, then Trueman will get to revive one of the destroyed Monsters on his side of the field. At the time, Austin controlled Volcanic Doomfire, which represents his father, and Volcanic Queen, which represents his mother. Though it tears him up inside, he chooses to save Volcanic Doomfire, reasoning that if he saved Volcanic Queen, then Trueman would attack it with the stronger Volcanic Doomfire. Trueman mocks him for choosing to save his father again and ultimately defeats him. Right before Trueman traps him in the World of Darkness as a penalty for losing, Austin hits the Despair Event Horizon and says he should have just let all three of them die.
