During the opening car chase, there are several scenes where the green Alfa Romeo will have damage on the sides - but in between shots, there is no damage. The same goes with Six's hat: on or off.
During the Florence car chase, the Alfa Romeo Giulia's driver's side mirror appears and disappears between shots after being clipped off by a truck.
During the 'giant magnet' sequence, characters arrive in the kitchen where all the knives, pots, etc. fly across the room and stick to the walls. As this was the third time the magnet was turned on, the kitchen should have already been in disarray.
Both during and after the final action sequence on the yacht & helicopter, it gets inexplicably dark outside, but by the time the crew makes it out a few hours later, it's broad daylight again.
Blood spurts onto Amelia's eyebrow and face, which disappears in subsequent shots.
Three should not have been affected by the laughing gas in the elevator. The insertion point for the filter on his gas mask would have sealed when the filter fell off, instead of exposing him to the gas.
The MINI Clubman used as a getaway in Hong Kong is left-hand-drive. Hong Kong does not allow any left-hand-drive vehicles to be registered and used on public roads.
The phone One is using to control the giant magnet on the boat should have some metal in it, unless he also invented a non-magnetic phone.
During the Firenze car chase an Italian police helicopter is seen flying over the roofs. The actual color and insignia of Italian police vehicles (including helicopters) is light blue with white stripes and not silver gray with red stripes.
The HK Police cars used in the film have yellow and blue Battenburg markings. Those cars are from the Traffic Branch. The actual HK Police cars used in that situation should be white with red stripes.
Just after #3 is identified on screen in the opening chase, the stunt driver for Dave Franco can be seen in a quick shot .
Mannequins can be seen in the shot where the green Alfa Romeo crashes in the forklift.
Shooting a hole through the glass wall of a swimming pool wouldn't let a person breathe. Water would stream out of the hole at first, and if a person were to, essentially, kiss the hole, the pressure from the water remaining in the pool would be enough to cause serious injury to the face.
The actor who portrayed a billionaire who became rich from the use of neodymium mispronounced it. Evidently, neither the director nor the editor knew the correct pronunciation either.
After Four slides down the basilica, when he is running on the roof, he says, "I see you," but his tongue is hanging out of his mouth at that moment.
(At around 19 min) When the car drive over the edge, there is a camera filming the fall, in the next shot, a little further away, when the car hits the ground, you can see the camera that filmed the fall, in front of the Infiniti car.
As One tries to scan the retina, the boom mic operator can be seen in the driver's window.
A crane shadow is momentarily seen on the road as two motorcyclists (who were mowed down in a previous shot) skid across it.
The cameraman is briefly reflected on a blue glossy part of the yacht, during its evacuation.
When One and Five make out in a close-up, the camera's shadow is visible drifting across their faces.
Reynolds announces they are going to Las Vegas to kill the 4 generals. In the next scene the camera pans over the roof of Ferrari World building in Abu Dhabi with the caption "Las Vegas"
In the opening scene, shots of Four running and cars chasing switch between Florence and Siena (passing famous landmarks like the Piazza Del Campo in Siena and the Florence Cathedral). Siena and Florence are 70 kilometers apart.
During the car chase scene in Florence, Italy there is a brief scene in which the Alpha Romeo crosses an oval like square with an orange building in the background. This square is actually the Piazza del Campo located in Siena which is over 30 miles/ 50 km from Florence. Twice a year the famous horse race the Palio is run on this square.