Factual error: When Hopper is running from the convenience store you can see Rite Aid in the background. You also see Honolulu police cars in the same scene. There isn't a Rite Aid in Honolulu.
Suggested correction: Not sure about this one. Honolulu is on Oahu, so I'm not sure what the police cars correction is, and there are Rite Aid stores on Oahu, and in Honolulu.
Where is (or at least was in 2012) the Rite Aid in Honolulu?
Rite Aid stores are in 18 states, and Hawaii is NOT one of them. I even went to the Rite Aid website and used the "store locator." When I wrote "Honolulu", the result was "no stores within 50 miles." (This would be currently, so the question below about 2012 remains unanswered).
Factual error: When Hopper orders to drop the port anchor during the final battle, the chain changes between being stretched and taut from scene to scene.
Factual error: Towards the end of the movie, an Australian F/A-18E Superhornet is shown destroying the aliens, complete with Australian pilot. Firstly, the Ensign displayed on his helmet is incorrect. Australia doesn't operate any of those aircraft, only 2 seat F/A-18F and older F/A-18A Classic Hornets.
Suggested correction: A close examination of the F/A-18s in this sequence shows the correct configuration for 'legacy' F/A-18s, including the distinctive straight engine intakes that is the most obvious difference between the F/A-18A to D models and the later F/A-18E/F Super Hornet. Therefore the aircraft do correctly resemble RAAF F/A-18A's. A better question is where they have come from considering that RAAF F/A-18s are not carrier capable or qualified.
Factual error: During the soccer match with Japan, Hopper is kicked in the face and had blood coming from his nose onto his lips and chin. Then while talking to a Japanese player the blood is gone, then a few seconds later when he makes the penalty kick the blood is back on his face.