SpongeBob and Sandy are practicing karate against each other. SpongeBob is carefully going around his house looking for her, until she jumps out. They fight, and have lots of fun. Sandy tells him that she will sneak up on him and fight him tomorrow. At The Krusty Krab the next day, SpongeBob thinks anyone or anything can be Sandy, so he is cautious and does not work much. When he strikes one of the customers, Mr. Krabs demands to know what is going on, so SpongeBob explains to him that he is doing karate.
Therefore, Mr. Krabs tells him to stop doing karate, or he'll have no choice but to fire him. Sandy attacks him, and though SpongeBob attempts to explain Mr. Krabs's warning, Sandy doesn't believe him. At that moment, Mr. Krabs sees this and thinks he is doing karate with Sandy. An angry Mr. Krabs comes out of The Krusty Krab and tells SpongeBob that he's fired. This upsets SpongeBob. Sandy quickly explains to him that SpongeBob tried to tell her, but she wouldn't listen. Mr. Krabs gives SpongeBob his job back. Mr. Krabs warns SpongeBob not to do anymore karate as he feels that it's poisoning his mind.
The two attempt to forget about karate, and go to the park. However, while slicing sandwiches, they begin doing karate again, Mr. Krabs catches them. SpongeBob admits the truth and explains that he can't help himself. He gives Mr. Krabs permission to fire him. However, instead of firing SpongeBob he finds that karate chops can replace knives. The next day Mr. Krabs has SpongeBob and Sandy slice Krabby Patties this way, earning him more money.
As of October 30, 2013, The Internet Movie Database (IMDB) gives this episode a rating of 8/10 based on 116 ratings by users. TV.com users give this episode a 9/10 based on 197 votes.
"Karate Choppers" was ranked #44 during the Best Day Ever event on November 9–10, 2006.
There is a game called "Kah Rah Tay" that is based on this episode on Nick.com.
On The Complete 1st Season DVD, this episode, along with "Plankton!," has a cast commentary.
This is the last episode to premiere in 1999, along with SB-129. It is also the last episode of the 1990s. It's also the last episode to air in the 20th century. The next episode, Sleepy Time, premiered in 2000.
There is a fish fishing for fish with a fishing pole at the Bikini Bottom Park.
When SpongeBob attacks Fred and sends him into the floor, some fish are shocked. One of the fish (who is gray with something purple on his face) is the fish that acts confused when he hears Plankton's squeaky voice in Walking Small.
The face on the hot sauce drop is Tom Kenny's face. In the Season 1 DVD commentary, he stated that he had to wear red makeup all over his face in order to make the hot sauce scene better.
A clip of this episode can be seen in the 2010 film Date Night.
SpongeBob went into the bathroom and thought he heard Sandy, but SpongeBob went into the men's room, so Sandy could not have been in there.
In this episode SpongeBob, is good karate master like Sandy. However, in other episodes, Sandy is much more skilled.
Throughout this whole episode, Sandy has three dots on her patch instead of an acorn.This has never been shown again on the series.
"MY LEG!" has become a popular meme on YouTube and many other sites on the Internet.It is also frequently used throughout the series.
This episode includes a rare instance in which SpongeBob defeats Sandy in a karate fight.
The mask that Sandy says is her "worst disguise yet" looks similar to the one that SpongeBob wears when he pretends to be Sandy's "pappy" in "Sandy, SpongeBob, and the Worm."
It is unknown if Sandy and SpongeBob ate the Krabby Patties because after fighting, (and making Krabby Patties) they were relaxing and the Patties were still on the ground.
When SpongeBob slices the first slice of salami, the mustard bottle is missing.
At the Bikini Bottom park, when Sandy karate chops SpongeBob's arm, SpongeBob doesn't have karate gear on, but in the next shot, SpongeBob has his karate gear on.
A second window was added to SpongeBob's pineapple home near the lower right corner. Before, there was only one window on the upper left corner.
In one scene where SpongeBob and Sandy are karate chopping each other, Sandy karate kicks SpongeBob into the background. SpongeBob yells "Curses!" and Sandy appears to be moving her mouth as though she is also saying it, though she could be mimicking it.
Mr. Krabs tells Squidward that he was in his office, however, the viewer will notice that Mr. Krabs' office is the first door on the left, and when he comes in, he's on the right. But when SpongeBob talks to him, Mr. Krabs is on his office side, next to Squidward.
When SpongeBob rolls Sandy into a ball, her helmet and flower disappear.
When SpongeBob goes into the bathroom (of the Krusty Krab), there is the "Please wash your fins" sign on it. Later, when SpongeBob is walking, it disappears.