Revealing mistake: When Daniel is running from Johnny and his gang after the bathroom incident at the dance, there's a lot of fog outside. If you look at one of the trees in the background, you can see that all the fog is being puffed out from behind the tree - obviously a fog machine.
Continuity mistake: We first see from the inside of the door (and therefore backwards) the instructions that Mr. Miyagi leaves for Daniel to paint the house. In the next shot we see the same note from the outside - from Daniel's viewpoint. Clearly they are two different notes. The left & right arrows switch directions, the drawings of the hands change, the position of Miyagi's signature changes, and the placement of some of the exclamation points changes.
Continuity mistake: In the final fight between Daniel and Johnny, there is a time when Johnny's head band falls off (after Johnny scores his second point). Right after it falls off, if you look quickly you can see it back on, then it goes back off. (02:00:50)
Suggested correction: That right unless there were a few bits of the scene cut where the referee gave it back to him.
Revealing mistake: When Daniel is about to paint the fence of Mr. Miyagi, Mr. Miyagi tries to catch a fly with chopsticks. Daniel tries as well. You can see that this "fly" is attached to a wire or a nylon string, moving like a pendulum and bounces as if someone's pulling the string.
Other mistake: In the semi-final where John Lawrence fights against Darryl Vidal, the female referee has major problems of what to do. When Lawrence gets his first point, the referee first raises her red flag (Vidal is wearing the red ribbon) but then swiftly changes her mind. And when Lawrence gets his third point, the female referee again incorrectly raises her red flag.
Visible crew/equipment: In the scene when Miyagi and Daniel are about to get into Miyagi's truck and drive to the Cobra Kai Dojo, Daniel is yawning and to the bottom right of him the boom mike can be seen for a few seconds.
Continuity mistake: After Daniel's little party at Miyagi's, they both go outside and Daniel sits in the yellow car and Miyagi walks up. In the shot from the front Miyagi has his hands crossed leaning on the car door, yet from the back he has his elbow leaning on the door, then back to just his hands on the door. (01:35:15)
Continuity mistake: When Daniel comes back from the restaurant having just seen Ali with Johnny, Daniel sits down next to Miyagi. When Daniel says, "Banzai," he does not have his arm resting on the small table, yet in the next closeup his arm is now on the table. (01:24:25)
Continuity mistake: When Daniel and his mum are in their apartment unpacking, the mum has nothing in her hands in one shot, and in the following shot she has a small red case. (00:06:55)
Revealing mistake: In the beginning where Daniel and his mom finally arrive at the new apartment, pay close attention to the wooden entry fence. Soon after Daniel's mother states, "This is the Garden of Eden," you can see Daniel's soon-to-be friend "Freddy" lining himself up behind the wooden fence prior to Daniel's mom opening the door.
Continuity mistake: When Daniel catches the fly with the chopsticks, he catches the fly in the middle of the sticks. When the shot changes, he now has the fly with the tips of the sticks.
Continuity mistake: In the scene where Mr. Miyagi teaches Daniel defensive moves, Daniel blocks Mr. Miyagi's punches with his right hand on the 'paint the fence' move. Daniel then leaves his right hand high, in a defensive position. This shot is taken behind Daniel, over his left shoulder. The next shot, a side view with Daniel on the right of the screen, shows Daniel's left hand held higher, as if he'd used that hand all along.
Continuity mistake: In the beach party scene when the boom box is thrown at Daniel he catches it with the speakers facing away from him, but when it was thrown the speakers were facing him.
Other mistake: During the final match, Johnny scores his second point with a forearm to Daniel's side. However it is incorrectly announced as a kick to the side. Johnny was on one knee at the time and in no position to kick him. Also, you can see Johnny throw a forearm and not a kick.
Continuity mistake: Before the dance in Mr. Miyagi's work area you can see the red shower curtain with the polka-dots that Danny wears to the dance hanging on the wall. After the dance, when Danny is in the work area after getting saved from the Skeletons, you can still see the shower curtain on the back wall.
Suggested correction: The mistake assumes Mr Miyagi only had one shower curtain. Many people have more than one to replace the current one when it's worn or so dirty with soap scum they are cheaper to replace than try to clean.
Audio problem: In the external shot of "The Orient Express Restaurant" where Daniel's mum sits down and says, "Guess what? I'm going to be training as a manager.", her mouth isn't moving at all.
Continuity mistake: At the beginning when Daniel is playing soccer on the beach, he has a huge sweat stain on the back of his shirt right before he runs past Ali. Moments later, when he runs away from Ali, the sweat stain has drastically reduced in size.
Revealing mistake: When Mr Miyagi saves Daniel from Johnny, you can see that it's not Pat Morita jumping over the chain fence, but his stunt double (Fumio Demura). (00:39:10)
Continuity mistake: In Daniel's first match, when he scores his first point, the bleachers are packed to capacity but just before the next point only 7 rows of seats are partially filled. The referee (with the red shirt) can also be seen sitting down in this shot on the right side, when she is actually refereeing the match).
Continuity mistake: When Johnny and his gang jump Daniel at the chain fence, Johnny smashes the sign on the fence, yet in the following shot the sign is there again, then the shot after its broke again. (00:39:15)
