Continuity mistake: Rumpelstiltskin looks completely different in this movie than he did in the previous film Shrek The Third; Prince Charming momentarily talks to Rumpelstiltskin in the tavern during the third film, and the character looks completely different, has a different voice and different demeanor.
Continuity mistake: During Andy's daydream at the beginning of the film, Mr. Potato Head has an eye patch over his left eye. When the daydream cuts back to reality we see that Andy has removed Mr. Potato Head's left eye to symbolize the eye patch. But when Andy's mum comes in with the video camera, his left eye is suddenly back in. (00:01:15 - 00:05:25)
Continuity mistake: When Lou and Nick are playing pool in the bar, Lou goes to break the rack and misses. When Nick goes to break them, the balls are racked in a different pattern. (00:50:10)
Factual error: They are present at Frankfurt, Germany. But with a closer look you see a cathedral at the right side. This cathedral and the central station are located in Cologne, Germany - they are about 220 km apart. (01:04:15)
Continuity mistake: Gamble and Hoitz get thrown to the ground when the accounting office explodes. In an overhead shot of them rolling around on the ground, Gamble's wooden gun has fallen from its holster and is lying on the ground. Cut to a side shot and the gun is back in its holster. Gamble had both hands covering his ears the whole time, he did not pick up the gun. Then comes another overhead shot, the wooden gun is again missing from the holster. (00:48:45)
Factual error: The day Carrie arrives in NY: June 11, 1986 was a Wednesday not a Tuesday.
Plot hole: When Astrid gets on Toothless for the first time, Toothless takes off uncontrollably and tries to scare her. Hiccup seems to have no control over him at this time. How is that so if with the new tail fin, Toothless cannot fly without Hiccup's precise control of the tail fin? That whole sequence would have fallen apart. This mistake was even admitted to on the DVD commentary. (00:53:35)
Continuity mistake: Just before Flynn cuts off Rapunzel's hair, there is a shot from behind him and he reaches up with his right hand to push her hair behind her ear. His arm is visible up to his forearm and the shackle is nowhere in sight. However, in the next, wide shot, the shackle is suddenly up around his wrist. (01:01:20)
Continuity mistake: In the dock scene where Rob Schneider kicks David Spade in the groin the first time for supposedly sleeping with his daughter, his good foot has a black shoe on it. Then as you see him kicking Daid Spade he has no shoe but is in bare feet, But when he falls down from the pain in his bad foot you can see that he now has a black shoe on his good foot again. (00:11:45)
Revealing mistake: When Jack is doing a search for "Andi Garcia" on Google, the links show up in the searches he does as purple and not blue which means that they have already been visited, despite the fact that he's supposed to be doing this search for the first time.
Continuity mistake: In the scene where Sophie is first walking out of the New Yorker building, her shirt is tucked in in the first shot, in the second it is untucked, and in the third it is tucked in again.
Continuity mistake: When the 3 guys are kicking a single guy with Kick-Ass defending him and a bunch of people behind watching the fight, the trashcan on the ground keeps changing positions between shots.
Other mistake: In a hockey game, Derek Thompson slams an opposing player into the wall and knocks out a tooth. Inexplicably, the tooth shoots straight up into the air and there is absolutely no blood on the tooth or around the player's mouth.
Continuity mistake: As Darren passes the cheese touch to the girl, she turns around in shock. In the next shot, she is standing still with everyone crowded around her running away, and Darren is no longer seen.
Factual error: Outside Seville, Cruise jumps off a bridge on a stall with a sign that reads "Especial en sardines". This is senseless text. The correct spelling should be "Especialidad en sardinas".
Continuity mistake: When Olive is at the ice cream store near the end of the film, she picks up a chocolate-coated cone off the counter and crushes it in her hand. However, in the next shot (as Olive walks away), the cone reappears intact.
Factual error: Milo gets out of the car to pump gas, but they are in New Jersey where pumping your own gas is illegal.
Other mistake: When the ride finishes, there is no sign of a safety bar in Gru's cart.
Continuity mistake: When passing the lion in Trafalgar Square approx one hour in, the motorcycle sidecar swaps sides.
Continuity mistake: In one of the final scenes of the movie, George Lopez and his wife are depicted on swings with two red wines placed on a table. The scene transitions into another couple and later George Lopez and his wife are shown again. This time they toast and drink the wine on their swings. However, in this scene the wine they are drinking is white.