Killjoy scientists say Spider-Man cannot exist.

University of Cambridge researchers found that it’s physically impossible for a man to scale walls — as a spider can — because people don’t have enough sticky surface area to support human weight.

People would need adhesives on 40 percent of their surface area to scale walls without any help. The key is maximizing surface area while minimizing volume.

In theory, researchers said, a person could walk walls with sticky shoes — size 114.