(at around 1h 22 mins) When Ethan is writing the calculations for the building jumps on the window, the math changes between shots.
When they are being attacked and shot at on the bridge, Ethan's back left jeans pocket is ripped. After recovering from the almost fall off the bridge, his jeans are no longer ripped.
(at around 1h 26 mins) When Ethan is in China to retrieve the Rabbit's Foot, the four guards on top of the roof clearly communicate and visually see each other. When sliding down the roof he only shoots two of the guards, leaving the other two alone. These guards would clearly see the two fallen guards and set off the alarm right away.
During the bridge battle when Ethan shoots down the drone, he initially brings the gun up to his left shoulder with his right hand forward. In the next shot, the gun is on his right shoulder with his left hand forward.
(at around 54 mins) When Davian is being kidnapped in the bathroom, as Hunt is coughing to kill time, the camera switches back between Hunt and the bodyguard, the tissue he is holding continually switches between his left and right hands.
Most of the dresses worn by the women, including Maggie Q, were far too immodest to be worn at the Vatican's St. Peter's Basilica. In particular, women may not have bare shoulders. Most of the attire would not even be acceptable in the museums.
(at around 23 mins) A defibrillator submits an electrical charge that only affects muscles. Therefore, the charge would never make it to the brain. To try and kill the implant, a direct charge to the brain would be needed and in doing so, kill the person.
(at around 43 mins) In the Vatican city, Ethan clips on what appears to be some sort of inductive wire tap over Ethernet cables to gain access to the internal security camera feed. An inductive type of tap that just goes around the entire cable would not work with Ethernet, as there are multiple pairs of conductors inside a single cable, each operating with differential signaling.
(at around 1h 7 mins) In the Bay Bridge attack as the missile detonates on Ethan's left side, Ethan is hurled to the left, not the right as one would expect.
When Ethan is running from the car that is about to be hit by a missile, the car explodes but the explosion does not push his back to fall face first, instead the explosion behind him pushes him to the side to hit the car.
The GPS coordinates N57,50 E21,00 are in fact a location in Baltic Sea and not "near Berlin."
This is done deliberately in movies in order to avoid identifying actual locations, similar to the practice of using 555 as the prefix for phone numbers.
(at around 1h 6 mins) In German, "IMF" would be pronounced "Ee em eff," yet the German commando in the helicopter pronounces it "Eye em eff." However, it would be perfectly normal for a German native speaker to pronounce it in English like he would for example "CIA" or "FBI".
When Ethan swings onto the roof in Shanghai, the security guards shout at each other in Mandarin. Although the Shanghaiese dialect is spoken in Shanghai, there are large numbers of "guest workers" in Shanghai, and Mandarin is widely understood. Moreover, the guards are reported to be former "Chinese Intelligence", and, as such, are likely to be drawn from all parts of the country, the majority of whom speak Mandarin.
(at around 1h 9 mins) When Ethan is fleeing the scene of the bridge attack in the Mercedes convertible, we see him steering with one hand and using his phone with the other, but the soundtrack indicates manual gear-changes are being performed. This can be explained by the type of gear box which is either a semi-automatic or Tiptronic.
While the IMF caravan is on the Chesapeake Bay Bridge-Tunnel with Davian, all of the vehicles with Virginia tags are labeled incorrectly. Virginia license plates consist of three letters, a hyphen, and four numbers (LLL-NNNN) not three letters as shown.
This is done deliberately in movies so as to avoid identifying actual license plates, similar to the use of 555 for phone numbers.
(at around 42 mins) During the infiltration of the Vatican, Ethan climbs on a thick wall beside a CCTV camera, turns it off, takes a picture of what it is seeing, prints it and hangs it before the camera before turning it back on. The Focal length of a CCTV camera is usually set to infinity, especially one that is taking a large view, meaning everything within 90 centimeters of the camera would be out of focus. The photograph was hung a few centimeters before the camera, that would make it largely out of focus.
(at around 56 mins) After they kidnap Davian, Ethan closes the lid of the drain. In the next shot when they are in the sewer, some light is coming from above. If the lid has been closed how can the light come from above?
(at around 9 mins) Ethan is told to meet 'at the crack of dawn' the next morning for the mission, but when Ethan appears the next morning it is obvious the outdoor shadows are near mid-day.
Ethan is lying on the gurney and he doesn't have any shoes on, when he breaks out of his restraints in the elevator he has boots on.
(at around 49 mins) When Ethan and Luther are using the machine to paint the Owen mask under the Vatican, the eye-holes in the mask stay white while the rest of the mask is painted. If the mask were really being painted, the head mannequin would have also be painted.
When Zhen is climbing out of the Lamborghini Gallardo, particular attention is given to her high heels. The footwell and pedal position of the Gallardo does not space not sufficient height to accommodate high heels.
When the Lamborghini Gallardo is blown up, there's a ring of liquid surrounding the car on the ground of the square. Presumably this is to contain the extent of the explosion.
On the back of the postcard Ethan gets from Berlin, the description of the motive says "Berliner Dom und Schlossbrüke" (Berlin Dome and Castle Bridge). "Schlossbrüke" however is misspelled. It should read "Schlossbrücke".
When the Security BMW flips, the second one brakes to miss it. Both brake lights are not working.
(at around 31 mins) The postcard sent from Berlin has a postage stamp with post-2001 Euro Currency on it. The postmark however says "Deutsche Bundespost" which ceased to exist in 1994. The mail business is called "Deutsche Post" since then. Also a real German postmark would look similar, but instead of "Deutsche Bundespost" would state the town (e.g. Berlin) in the top half and the ZIP-Code (e.g. 10001) in the bottom half of the outer circle.
When they're in the sewer, Zhen says "Oh it's such a nice car". Hunt pulls off the Davian mask and then the voice-altering strip and says "And yet..." (in Davian's voice), "Do it" (in his own voice). His mouth does not move on the words "And yet".
(at around 1h 35 mins) When Ethan's team return from China and the camera pans around the airplane the entire crew can be seen in the red painted part of the plane.
(at around 1h 17 mins) When Ethan is escaping from IMF headquarters and climbing up the elevator shaft cable, you can see the back of his coat being lifted up from the cord that is lifting him.
(at around 31 mins) Camera operator visible in far left corner of Ethan's sunglasses at the funeral service.
Ethan tackles Owen as he is loading a pistol to shoot Julia. They tumble together through a glass door. As Owen lands on his back and drops the pistol, Ethan (his stuntman/Cruise himself) can be seen tapping Philip Seymour Hoffman on the chest as if to say "okay" or "good job"
Luther says that the Vatican is "surrounded by a 60-foot wall which is monitored 24/7." In fact, access to the Vatican is completely open via St. Peter's Square.
(at around 1h 9 mins) The attack to release Owen Davian is set on Virginia's Chesapeake Bay Bridge-Tunnel. After the attack, Ethan Hunt jumps into a convertible and in a very short period of time drives across the 14th Street bridge toward the Jefferson Memorial, which is about a 3 hour drive from the Bay Bridge-Tunnel (The bridge-tunnel connects the Delmarva Peninsula with southeastern Virginia).
Nowhere near Berlin is there a wind park like the one in the movie. Also the geography in the background with mountains is incorrect to what Berlin and its surrounding areas look like.
(at around 1h 10 mins) When Ethan is in the Mercedes convertible fleeing the scene of the bridge attack, he passes several Virigina State Police cars with red and blue roof lights headed in the opposite direction. However, Virginia law states that police vehicles in Virginia can only have blue roof lights (red lights are reserved for fire trucks, ambulances, and rescue vehicles).
(at around 1h 11 mins) After Julia is kidnapped, Ethan leaves the hospital and AMR ambulances are in the background. AMR does not provide ambulance service for D.C. or Virginia.
(at around 1h) When Davian is hanging head-first out of a moving plane in the face of a deafening roaring wind, he still manages to hear Luther call Ethan by name inside the plane.
Davian's translator is unable to speak when disguised as Julia because of the duct tape over her mouth. However, the duct tape is attached to the mask, leaving her own lips free to move underneath it.
(at around 1h 22 mins) Luther states Ethan is going to use a "fulcrum" to swing from one building to another in order to steal the Rabbit's Foot when in fact what the team uses is a pendulum. A fulcrum is a point for a lever to act upon, a pendulum swings under the influence of gravity.
When Ethan is looking at the team that has been put together for the rescue mission, Luther Stickell's details come up, however, his surname is misspelled with only one L (Stickel).