There are 4 Simple Keys in Hollow Knight.

Quick Scoop

  • Total number of Simple Keys: 4.
  • Each Simple Key is single‑use and opens one “simple lock” only.
  • You don’t need to grab them in any particular order; they’re interchangeable.

Where they’re used (overview)

  • Royal Waterways entrance from the City of Tears.
  • Jiji’s house cave to the right of Dirtmouth, beyond the graveyard.
  • Pleasure House door in the City of Tears.
  • Godseeker’s cocoon in the Junk Pit (leads into Godhome content).

Tiny story-flavored note

Think of the Simple Keys as four ancient little tickets into Hallownest’s more secret corners: sewers, a hidden confessor’s den, a decadent bathhouse, and the strange realm of the Godseeker. Each one gets swallowed by the lock when used, so planning which doors to open on a first playthrough can feel like its own mini-strategy puzzle.

Mini FAQ

  1. Can you get more than 4?
    • No, there are only four obtainable in a normal run.
  1. Can you lock yourself out of content?
    • Not permanently, as there are exactly four keys and four simple locks, so you can eventually open everything in that save file if you collect all of them.
  1. Are they required to beat the game?
    • You can finish the main ending without using all of them, but they’re very helpful for extra content, shortcuts, and late‑game challenges.

Information gathered from public forums or data available on the internet and portrayed here.