Continuity: When McClane knocks the fridge over so it's on its side near the start, his head is above the top (side) of the fridge. Camera cuts and it is well below the top (side) of the fridge.

Continuity: In the traffic jam in the beginning of the film (right after all the lights have changed to green), the car next to McClane's is black/dark. But a few seconds later when you see it from a helicopter, it has changed to white.

Continuity: During the traffic jam scene, when the truck crashes against the taxi, the view inside McClane's car shows the taxi colliding against the car, dragging it away violently. From the aerial angle, the taxi doesn't touch McClane's car at all.

Continuity: At the end of the scene where Bruce Willis's own car is involved with a crash between a dustcart and taxi you can see his driver's door opening during the aerial shot after he has left the location.

Continuity: When McClane first brings Farrell to the Cyber division, McClane has a cut over his eyebrow that he gets from a fight scene later in the film. [This mistake is pointed out in the DVD audio commentary: this scene was filmed after said fight scene was completed.]

Trivia: Bonnie Bedelia makes a cameo as John's ex-wife, Holly, via a picture of her driver's license.

Continuity: When McClane is driving the police down the ramp to the tunnel so he can elude the helicopter, the car's windshield doesn't have any bullet holes or cracks in it, even though it did just a few seconds earlier.

Continuity: When McClane and Farrell are fired upon during the escort to DHS, Agent Johnson is killed and slumps against the steering wheel. In the next shot he is alive, looking back through the car's rear windshield, and jolts forward with the car's impact with the car in front of them.

Continuity: John's face is all bloody after he rolls from the car and "kills a helicopter with a car". The blood on his face constantly changes during the shots. Sometimes there is blood all over his face, sometimes there is quite a bit less. Sometimes he has blood streaming from the cut on his nose, sometimes there is nothing on his nose. The blood changes back and forth, so it's not just him wiping the blood away from his face (and his hands are by his sides during all the shots).

Continuity: In the scene where McClane rebuffs Ferrell for thinking it would be cool to do the firesale, you can see pipes for firehoses right behind McClane. When the shot changes to a long alley shot, the pipes are a good ten feet away, but when it reverts back to a closeup, the pipes are back to right behind McClane.