Can Spiders Walk on Glass?

Are spiders actually capable of climbing glass? The answer is yes, but only a few species of spiders naturally can.

Spiders have small hairs at the end of their legs, which make them stick to many surfaces. Spiders are able to walk upside down, and they can even walk on wet or slippery surfaces. In fact, the electrostatic van der Waals forces produced by these tiny hairs are strong enough to allow them to carry up to 170 times their body weight.

However, some tarantulas do learn how to climb glass. Tarantulas have eight legs, which are equipped with sticky silk that anchors them down. These silk strands are a key factor in a tarantula’s ability to climb glass.

Another factor that allows a tarantula to climb glass is its silk-shooting feet. Some tarantulas also have small silk glands and fuzz on their legs. This sticky material makes the tarantulas more agile and able to climb walls.

One of the best ways to figure out if a spider can climb glass is to look at the texture of the surface. A smooth glass surface is tougher for a spider to climb than a rough one. Therefore, smaller spiders with more flexible leg hairs are more likely to be able to climb.

Some spiders can climb vertical windows, but most do not. If you have a large, heavy spider, you are unlikely to see it walk across a window.

While a lot of people believe all spiders are capable of climbing, this is not true. The majority of IRL spiders cannot climb smooth or wet surfaces.