Theraphosa blondi—better known as the Goliath Birdeater or Goliath Bird-eating Spider—is the largest spider on Earth, with legs that can reach up to a foot in length. The Huntsman Spider can be larger however and is typically considered the largest spider by leg-span.
The image of those two spiders alone is enough to invoke nightmares. However, both aren't dangerous to humans. The Huntsman Spider can cause swelling and be painful, but it won't kill you. The Goliath Birdeater on the other hand can barely break through your skin and may not even release venom when it does so. Nonetheless: the size of those two spiders alone is enough to trigger a panic attack. That is, until you wonder: could there be spiders that are even larger?
Earth's a mysterious place. Each year, we discover many new species of animals and plants, which is a good reminder that we don't know anywhere near as much as we think we do about our home. Coupled with the history of reports of giant earwigs, birds, ants, octopi, squids (which turned out to be true), sharks, and so on: the concept of a giant spider isn't too far fetched—is it?
Maybe, maybe not. There is a cryptid that's said to be a giant spider: J'ba Fofi. It's associated act is Mokele-Mbembe; the names of both cryptids hail from the same the native Baka people. Unlike the latter however, J'ba Fofi didn't appear in 2019's Godzilla: King of the Monsters.