Encyclopedia SpongeBobia
Encyclopedia SpongeBobia

SpongeBob's brain is an internal organ that first appears in the episode "Plankton!" This fact is also mentioned in the audio commentary for that episode.


It has many different appearances. It is most commonly pink. Depending on where it appears (including episodes, movies, and shorts), his brain can look and function quite differently.

Role in series


Plankton invents a device that allows him to control others' brains. It works partially on SpongeBob's brain, although SpongeBob seems to still be in control of his thoughts and some of his actions.

"Scaredy Pants"

Patrick shaves SpongeBob's head down to his brain in order for him to dress like a round-headed ghost.

"I'm with Stupid"

SpongeBob shows Patrick, Marty, and Janet a picture of his brain as a way to prove that he is in fact intelligent.

"Welcome to the Chum Bucket"

Plankton puts the brain into a robotic suit, and it seems to keep its personality even outside of SpongeBob's body.

"Mermaid Man and Barnacle Boy IV"

The Bikini Bottomites go inside SpongeBob after they are shrunk by Mermaid Man's belt, and they see some of his organs including his brain.

"Snowball Effect"

It is mentioned and seen in Squidward's thoughts. When SpongeBob and Patrick claim they will knock each other's brains out in a snowball fight, Squidward imagines the scenario, in which Patrick throws a snowball at SpongeBob and his brain falls out.

"Squilliam Returns"

The inside of SpongeBob's brain is seen in this episode. Inside, there are miniature figures resembling SpongeBob, and there are areas resembling an office and a bathroom. When Squidward pretends to own a five-star restaurant, the miniature SpongeBobs delete all of SpongeBob's thoughts and memories so he will only think about being a successful waiter.

"Bummer Vacation"

SpongeBob very briefly pops his brain out of his head to show mentally he can stay away from work.

"Night Light"

It briefly appears when SpongeBob rolls his eyes into the back of his head to light up the dark inside him.

"Bucket Sweet Bucket"

When SpongeBob fetches water pipes for Plankton's redecoration, one of them goes through SpongeBob's head and knocks out his brain.


When a jellyfish is first interested in the noises which the wind makes flying through SpongeBob's holes, it flies into him and his brain is in view.

"House Fancy"

Before the episode, the brain was borrowed by Patrick briefly, and he gives it back to SpongeBob during the episode.

"Krabby Road"

Plankton has a device that is able to play music from different formats; one of them is "brain," and, in hopes of hearing a song about the Krabby Patty secret formula, Plankton connects SpongeBob's brain to the machine. This results in SpongeBob singing the music selected from the machine dial.

"Penny Foolish"

The brain falls out of SpongeBob's head by Mr. Krabs' search of SpongeBob's 'penny'. It starts crawling on a pair of legs similar to those of an insect. They both chase after it, showing that SpongeBob can still move and function without it. The brain also has the ability to squirt some sort of liquid at SpongeBob. SpongeBob manages to grab it and persuades it to crawl back into his head, revealing to Mr. Krabs that he is a "brain whisperer."

"Nautical Novice"

SpongeBob learns the history of boating by literally putting his notes about it into his head, where it falls onto his brain.

"Porous Pockets"

While SpongeBob is wearing headphones, Patrick pulls on them, accidentally ripping off the top of his head and revealing his brain.

"I ♥ Dancing"

SpongeBob claims to have music on his mind, and he takes his brain out of his head. It is literally playing music like a radio, and it even has a radio dial that SpongeBob uses to change the song.

"Stuck in the Wringer"

When SpongeBob takes a shower, he uses soap to clean his brain.

"The Inside Job"

Plankton again goes inside SpongeBob, hoping to get the Krabby Patty secret formula from his brain.

"Kracked Krabs"

In this episode, Mr. Krabs suggests that SpongeBob keep his brain peeled. SpongeBob reacts by literally peeling the top of head to reveal his brain.

"SpongeBob's Last Stand"

When Mr. Krabs says that he and SpongeBob will give Plankton a piece of their minds, SpongeBob literally tears a piece off of his head to reveal his brain.

"A Day Without Tears"

When Squidward tries to make SpongeBob cry, the inside of SpongeBob's brain is shown. The brain apparently has a large dam built inside it. SpongeBob's tears cause it to collapse and the tears overflow the city of Bikini Bottom, being a metaphor for SpongeBob being no longer able to hold in the tears.


SpongeBob's blue brain with the earworm.

When Sandy was telling SpongeBob that he had an ear worm in his head, the brain is shown. Additionally, the brain is blue instead of pink in this appearance.

"It's a SpongeBob Christmas!"

Sandy uses an X-ray to display SpongeBob's brain along with his heart, citing his brain's small size as part of the reason why Jerktonium doesn't work on him.

"Séance Shméance"

SpongeBob's brain is shown to have drawers resembling those in a filing cabinet, and SpongeBob reaches inside his head and looks through them to try to learn what a customer's order means.

"SpongeBob You're Fired"

When SpongeBob is unemployed, he both figuratively and literally starts to fall apart, and his brain falls out of his head.

"Yeti Krabs"

When Squidward pretends to be a Yeti Crab in addition to the real Yeti Crab, SpongeBob's brain is shown bursting due to his horror.

The SpongeBob Movie: Sponge Out of Water

Plankton once again goes inside of it, and it once again is dark pink and smaller. Inside the brain is a gigantic space with SpongeBob's extremely happy thoughts, including the popsicles. This huge amount of happiness drives Plankton insane.

"Whirly Brains"

This episode revolves around SpongeBob's and Patrick's brains. They both use their own brains as Whirly Brains, an invention where one's own brain can fly and be controlled in the same way that a normal person would to a remote-control helicopter.


After Patrick walks over SpongeBob and splits him in half, SpongeBob's brain can be seen inside of him.

"The Getaway"

SpongeBob pulls out his brain during the episode and mixes it around. When he puts his brain back in his head, he starts laughing like a crazed maniac and drives his boat in a dangerous manner.

"The Legend of Boo-Kini Bottom"

The Flying Dutchman goes inside it to find a world of colorful happiness, similar to the second movie's version. The interior of the brain drives the Dutchman insane.

"Old Man Patrick"

It appears when SpongeBob starts doing a trance.

"Library Cards"

SpongeBob pokes his brain out of his head when he is telling Patrick that a library is a playground for your mind.

"Call the Cops"

After being called an idiot by Helen the Felon, SpongeBob splits apart in shame, revealing a very tiny brain.

"The Grill is Gone"

SpongeBob's brain appears when he is telling Mr. Krabs that he has the heart of a child.

"The Nitwitting"

When SpongeBob enters the Empty Head Society, he removes his brain by detaching it from its stem. This causes him to act similarly to the other members of the society, but he still retains some of his intelligence because his stem is intact. He tries to water his brain stem, but this causes it to burn out. SpongeBob remains without his brain until Patrick brings it back to him. His brain is shaped like a cube throughout this episode.

"Lighthouse Louie"

After being outsmarted by Louie and kicked out of the lighthouse, SpongeBob makes a comment about his "superior sponge brain." SpongeBob's brain is shown dancing before a gust of wind knocks it over.

"There Will Be Grease"

SpongeBob's brain is exposed after he scrubs grease from the ground.

Role in video games

SpongeBob's Game Frenzy

It is seen to get SpongeBob's eyeballs in the right place.

SpongeBob's Atlantis SquarePantis

SpongeBob mentions that his brain needed a rest.

Nicktoons Freeze Frame Frenzy

SpongeBob's brain reappears in the second level referencing the episode "Scaredy Pants."

Creature from the Krusty Krab

SpongeBob's brain reappears in the level "Hypnotic Highway," referencing the episode "Scaredy Pants."

Tracks of Terror

His brain can also area to build a roller coaster alongside with the Flying Dutchman's ship.

SpongeBob's Truth or Square

SpongeBob mentions that his brain is firing something.

The SpongeBob SquarePants Movie video game

In the PC version, when the Robot SpongeBob was chasing SpongeBob in the Chum Bucket, SpongeBob's brain can be seen.

SpongeBob HeroPants

His brain appears as a level to get the last page of the Magic Book.



Every Time We See SpongeBob's Insides 💀