Plans A-Y - These are all plans in folders that Plankton had employed before, and all had failed.
Plan Z - The one plan that Plankton missed. This one was more evil than the rest and even lemon scented. He used this to steal King Neptune's crown, and put the blame on Krabs so King Neptune can freeze Krabs, then Plankton gets his hands on the formula, and brainwashes Bikini Bottom's residents. However, he does not count on SpongeBob and Patrick, and after they retrieve the crown from where Plankton hid it, and with some help from David Hasselhoff, the two bring it back in time. When Plankton orders his minions to annihilate SpongeBob, he destroys their helmets with heavy metal music. Everybody in Bikini Bottom, Sandy, Scooter, Nancy Suzi Fish, Monica, and the rest of the Bikini Bottomites step on him and squish him a lot. He is then arrested.
Plankton! - Enters SpongeBob's mind and makes him steal a Krabby Patty.
Sandy's Rocket (seen only in chapter book based on episode) Plankton tries stealing it from the Krusty Krab during the night, only to be caught by SpongeBob and Patrick.
Culture Shock - Pretends to be a magician for The Talent Show, and asks for a volunteer from the audience. He steals a Krabby Patty from a customer and attempts to run off with it. Mr. Krabs stops him, and Plankton tries to disappear within fire, but ends up burning himself.
F.U.N. Tries to steal it again. Then pretends to befriend SpongeBob and steals a Krabby Patty from his hand while they're watching a movie. Plankton fails when he runs into the wall behind the movie screen.
Walking Small - Tries to make Goo Lagoon the site of his new fast food restaurant, The Mega Bucket. It almost works when he tricks SpongeBob into making civilians leave the beach by being aggressive, but SpongeBob's kindness brings them back.
Imitation Krabs - Comes to the Krusty Krab dressed up as a robot man and says he will give SpongeBob $1,000,000 for the Krabby Patty formula. Later on, builds a robotic Mr. Krabs, which he uses to attempt to get the formula out of SpongeBob.
Welcome to the Chum Bucket - Cheats in poker, and makes SpongeBob his fry cook to get Krabby Patties. When SpongeBob refuses to make Krabby Patties, he takes SpongeBob's brain out and puts it in a Robot SpongeBob, but it's SpongeBob's brain that's in the robot, and SpongeBob became lazy while at the Chum Bucket.
The Algae's Always Greener - Hides inside a ketchup bottle, but he gets shot out without getting to the Patty. Then, he tries the Switch-lives-just-to-know-what-it's-like-O-Microfier to be in Mr. Krabs' life.
Party Pooper Pants - When asked by Mr. Krabs what his topic card says, Plankton says "discuss the secret ingredients to the krabby patty formula" while the card says "where are you from?". Backfires.
This is famously one of the most minor and short schemes of the series and holds the shortest foil of it after 8 seconds.
Plankton's Army - Being a cockroach, but squished by Mr. Krabs. Then gathers relatives to steal the formula.
Fear of a Krabby Patty - Forces the Krusty Krab to open 24 hours and orders 10,000 Krabby Patties, thus causing SpongeBob to go insane out of exhaustion, and become irrationally terrified of Krabby Patties. He then makes himself into a psychiatrist and invites SpongeBob to tell him about the formula, but backfires when SpongeBob repeatedly crushes him with a piano, resists his attempts, and his work proves too well and inadvertently actually work and cure SpongeBob.
Krabs vs. Plankton - Attempts and fails to steal the formula again, then fakes injuring himself after slipping on the Krusty Krab's recently mopped floor and sues Mr. Krabs. He negotiates with Krabs for the secret formula during the trail only to fail when SpongeBob makes him confess.
Wishing You Well - Wishes on the Eugene Krabs Memorial Wishing Well to be taller in order to crush his enemies. Later succeeds, thanks to SpongeBob and Patrick when they struck magic.
New Leaf - He builds a gift shop. Then, he pretends to be friends with Mr. Krabs and get the formula which is a fake.
Best Frenemies - With the help of Mr. Krabs, find out the secret recipe to Kelpshakes, and partially re-befriends Krabs. At the end, he tries to steal the formula again. Feeling nostalgic, Mr. Krabs gives him a head start.
Friend or Foe? - Makes a cake for Mr. Krabs (since it his birthday). Then at the end again, he attempts to make Mr. Krabs cry then steal the formula.
Spy Buddies - Mr. Krabs and Plankton switched lives and try the different way and SpongeBob and Patrick become spies for the fake Mr. Krabs, but after a series of events the real Mr Krabs steals the formula back.
Tries to steal a Krabby Patty while everyone is distracted skating on the ice. Fails when he steals a patty from the local hockey team and can't escape the Krusty Krab.
Uses the Krusty Krab thermostat to freeze Mr. Krabs, SpongeBob, and the customers. Fails when he gets cocky, falls off the thermostat, and Mr. Krabs freezes him.
Bucket Sweet Bucket - Redoes the Chum Bucket, and makes SpongeBob, Patrick, and Squidward work so he can go to the Krusty Krab and steal the formula. Fails again when SpongeBob and Patrick replaced it by the Krusty Krab. The Chum Bucket is mainly destroyed at the end.
Goo Goo Gas - Dresses as a pepper shaker to steal the formula. Then, he creates a gas to turn Mr. Krabs into a baby and tries to steal the formula without "Baby" Krabs to notice. In the end, all the babies start playing around with Plankton, and he fails once again.
Mermaid Man vs. SpongeBob - He makes a shampoo that hypnotizes Mermaid Man and Barnacle Boy and makes them talk badly about the Krabby Patty and advertise the Chum Bucket, causing a large number of customers to come. This fails when SpongeBob has Mermaid Man and Barnacle Boy eat two Krabby Patties and use fiber to digest them, causing them to come back to normal.
Banned in Bikini Bottom - Since the Krusty Krab is banned, he tries to celebrate. Then he finds out there is a secret Krusty Krab, so he calls the police.
Stanley S. SquarePants - At the end, Plankton hires SpongeBob's cousin, Stanley, thinking that Stanley will be able to help him in stealing the secret formula as he has SpongeBob's own flesh and blood, and the fact that he knows nothing about Krusty Krab and Chum Bucket rivalry, so he'll fall for it. But in the end, Stanley blows up Plankton's restaurant as he is a terrible employee, as seen earlier in the episode. The episode ends with Stanley saying " Sorry, boss."
Krabby Road - He heard SpongeBob singing a song with lyrics as the formula so he creates a band.
Spongicus - Tears down the Chum Bucket and creates a stadium to keep custumers. Tries to boil Mr. Krabs in a giant bisque. (Mentioned by Karen)
Chum Caverns - He builds an underground restaurant named the "Chum Caverns" to attract customers. It was successful, but was eventually destroyed.
Someone's in the Kitchen with Sandy - Gets inside bun and tries to steal formula. He ends up going home inside Sandy's helmet, and steals Sandy's pelt to disguise himself and attempt to get the formula.
The Inside Job - Plankton goes in SpongeBob's body and uses a device to try and absorb SpongeBob's knowledge about the secret formula. Plankton fails when he ends up absorbing SpongeBob's personality as well and becomes a plankton-like SpongeBob himself. Upon escaping SpongeBob's body Plankton runs into Patrick and accidentally absorbs his personality, thus causing him to forget the secret formula and become a Plankton-like version of Patrick.
SpongeBob's Last Stand - He designs a highway (Shelly Superhighway), that would run straight over The Krusty Krab and end at The Chum Bucket. This plan was starting to be successful as Mr. Krabs almost sold the secret formula to Plankton but ended up unsuccessful when all of the Jellyfish of Jellyfish fields stung Plankton and SpongeBob and his friends destroyed the highway.
Gramma's Secret Recipe - Plankton dresses in his Grandma's clothing so he can trick SpongeBob and steal the Krabby Patty Recipe.
Buried in Time - After witnessing Mr. Krabs put a copy of the Krabby Patty secret formula into a time capsule, Plankton goes after the buried time capsule and drills a hole in it to try to get the formula. He gets the formula, but Squidward steps on him, making him swallow the bottle.
The Other Patty - Mr. Krabs and Plankton unite in their dislike of a new eatery called the Flabby Patty, and work together to steal its recipe.
Frozen Face-Off - Plankton creates a sled race and tries to get everyone in Bikini Bottom to join, so nobody will see him steal the Krabby Patty recipe.
Sweet and Sour Squid - Plankton attempts to strike up a friendship with Squidward in order to get the secret formula.
Walking the Plankton - Plan B: Plankton goes on a cruise with SpongeBob and Mr. Krabs in order to get the formula.
Plankton's Good Eye - Plankton grows a second eye in order to have better changes of stealing the formula. However, this plan was a failure as the eye from SpongeBob changed his personality.
Fiasco! - Plankton steals the art thinking it's the remains of a Krabby Patty hoping to revert it back into a regular Krabby Patty.
Free Samples- Plankton gives the customers fake Krabby Patties so that they wouldn't eat at the Krusty Krab anymore. But fails when Mr. Krabs gets them back.
Karen 2.0 - Plankton makes another Karen and Karen gets mad. Finding her parts in a box, Mr. Krabs makes Karen the cashier at the Krusty Krab. When Plankton tries to get into the Krusty Krab with Karen 2.0, She and the original Karen get into a fight, however during the fight, Karen 2.0 runs over Plankton and the original Karen, distressed, finishes off Karen 2.0 and the runs over to Plankton's side. After Plankton is revealed to be okay, Karen runs out of battery. Using batteries from the now dead Karen 2.0, Plankton revives Karen, and then they walk back to the Chum Bucket together.
For Here or to Go- Plankton uses his technology to successfully win a free Krabby Patty from Mr. Krabs. However, at the end, this plan failed as Karen actually scanned the insides of Plankton rather than just the patty itself.
Chum Fricassee - Plankton hires Squidward into making good tasting chum to run the Krusty Krab out of business.
Move It or Lose It - Planktons tries everything (including giving away free money) to help bulldoze the Krusty Krab.
Eek, An Urchin!: Plankton attempted to fool Mr. Krabs by wearing some glasses but was trampled by the fleeing customers. He then found out that it was a sea urchin causing problems and agrees not to steal the Krabby Patty secret formula until the urchin is gone.
Phase 1: Infiltrate the Krusty Krab: Plankton successfully enters the Krusty Krab through a fax machine.
Phase 2: Sabotage: Plankton saws off a bit of SpongeBob's spatula and when SpongeBob tries to flip a Krabby Patty, it breaks.
Phase 3: Give SpongeBob a New Spatula: Plankton waits for SpongeBob at Harvey's Spatula Emporium and offers to give SpongeBob a new spatula. At the Chum Bucket, Plankton gives SpongeBob the Majestic Sizzlemaster.
Phase 4: Gain SpongeBob's Trust: Plankton, using a voice modifactor, talks to SpongeBob through the Sizzlemaster and hopes to gain his trust. This is the longest phase due to SpongeBob not trusting anyone with the grill. Plankton finally manages to get SpongeBob to take the Sizzlemaster back to his house completing this phase.
Phase 5: Further Gain SpongeBob's Trust: Plankton, as the Sizzlemaster, does various of house work in order to gain SpongeBob's trust. Back at the Krusty Krab, Plankton finally manages to get SpongeBob's trust in working the grill completing this phase.
Phase 6: Burn All of the Krabby Patties: Plankton, as the Sizzlemaster, then burns all of the Krabby Patties and convinces SpongeBob to get the Krabby Patty Secret Formula to make more. However, Mr. Krabs finds out it's Plankton's doing and tricks him into making an explosive formula making this overall plan a failure.
Jailbreak!: Plankton attempts to steal the Krabby Patty Secret Formula by having his cellmates, who are all a fan of him and his chum, break into the Krusty Krab. They were successful in breaking in but Plankton and his cellmates were soon arrested by the Bikini Bottom Police Force marking this plan as a failure.
It Came from Goo Lagoon: Plankton attempts to steal the Krabby Patty Formula by using the giant purple goo bubble he literally created by opening the crack in the Goo Lagoon sea floor but fails when a dynamite exploded in his sub once he was reading the fake formula he got from Mr. Krabs.
Creature from the Krusty Krab - He turns a krabby patty crumb into a huge Krabby Patty that comes alive and tries to eat him. He then makes himself huge to get revenge on the Patty and in the process also destroys the Krusty Krab.
Nicktoons Racing - Takes up the title of the mystery rider who has a black car (faster and more control overall than the other nicktoons) and participates in the race where the prize is a lifetime supply of Krabby patties. When the game is beaten with good results, he is revealed to be the mystery rider, and says his tagline: "Well, this stinks!".
Though Plankton loses the formula back all the time, it is unknown why he never made a copy for backup.
Plankton's plans that don't involve stealing the formula are usually the ones that are close to success.
There have been times where his aim is not to steal the formula, as in Atlantis SquarePantis, he aims to rule Atlantis and kill the fellow tourists.
Although there are simpler alternatives for stealing the formula, Plankton always chooses completely illogical and complicated plans. For example in Plankton's Army, he uses a robot to pay a dollar bill for coral bits and jumping out of the dollar to surprise Mr. Krabs instead of programming the robot to buy a Krabby Patty.
Though given the fact that Mr. Krabs was already suspicious of the robot, he probably knew that programming it to buy a Krabby Patty would have exposed him.