Factual error: As a trash compactor Wall-E does not function logically. When he fills his chest compartment with garbage and runs his internal compactor, the cube that exits his body is the same volume as the trash he puts in, despite that trash having been compacted. He does not add extra trash to fill the empty space after running the compactor - there are three scenes that show him filling up only once with loose garbage and then ejecting a densely compacted cube. (00:02:30)
Suggested correction: You haven't noticed the exact shape of his body. The back sticks out a tad. Garbage fills the space and the back pushes in to compress it.
Factual error: In the very first scene a giant squid swims past Fujimoto. It swims in the wrong direction however, with its tentacles in front. In reality squid swim backwards.
Factual error: Near the beginning of the film, Calico is sitting with a cat on his right shoulder. Their reflection is shown in the glasses of a man directly opposite. The reflection shows Calico and the cat in the same position instead of being reversed, as a reflection would be. (00:04:30)
Factual error: When Moto Moto and Gloria were digging for water, they threw all the jewels and gold into a pile. The gold in the basket would weigh more than 1200 pounds. Also, real gold comes fused to other rock and rarely in pure form.
Factual error: After Tigress tells the backstory of Tai Lung the scene transitions from her being a cub to an adult. Young Tigress' stripes don't match the pattern of Adult Tigress. Tiger stripes don't change with age.